Glossary of chess

This page explains commonly used terms in chess in alphabetical order. Some of these have their own pages, like fork and pin. For a list of unorthodox chess pieces, see fairy chess piece; for a list of terms specific to chess problems, see chess problem terminology; for a list of chess related games, see chess variants.

Contents:		A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Absolute pin

A pin against the king, called absolute because the pinned piece cannot legally move as it would expose the king to check. See relative pin.

Active

Describes a piece that is able to move or control many squares. See also passive.

Adjournment

Suspension of a chess game with the intention to continue at a later occasion. Was once very common in high-level chess, often soon after the first time control, but the practice has been abandoned due to the advent of computer analysis. See Sealed move.

Adjudication

The process of a strong chess player deciding on the outcome of an unfinished game. This practice is now uncommon in over the board events, but does happen in online chess when one player refuses to continue after an adjournment.

Adjust or j'adoube

To adjust the position of a piece on its square without being required to move it. Adjustment can only be done when it is the player's move and the adjustment is preceded by saying "I adjust" or "j'adoube".

Advanced pawn

A pawn that is on the opponent's side of the board (the fifth rank or higher). An advanced pawn may be weak if it is overextended, lacking support and difficult to defend, or strong if it cramps the enemy by limiting mobility. An advanced passed pawn that threatens to promote can be especially strong.

Alekhine's gun

A formation in which a queen backs up two rooks on the same file.

Algebraic notation

The standard way to record a chess game using alphanumeric coordinates for the squares.

Amateur

The distinction between professional and amateur is not very important in chess as amateurs may win prizes, accept appearance fees, and earn any title including World Champion. In the 19th century, "Amateur" was sometimes used in published game scores to conceal the name of the losing player in a Master vs. Amateur contest. It was thought to be impolite to use a player's name without permission, and the professional did not want to risk losing a customer. See also NN or N.N.

Analysis

Study of a position to determine best play for both sides.

Annotation

Commentary on a game using a combination of written comments, chess symbols or notation.

Announced mate

A practice, common in the nineteenth century, where one player would announce a sequence of moves, believed by him to constitute best play by both sides, that led to a forced checkmate for the announcing player in a specified number of moves (for example, "mate in five").

Antipositional

A move or a plan that is not in accordance with the principles of positional play. Antipositional is used to describe moves that are part of an incorrect plan rather than a mistake made when trying to follow a correct plan. Antipositional moves are often pawn moves; since pawns cannot move backwards to return to squares they have left, their advance often creates irreparable weaknesses.

Anti-Sicilian

An opening variation that White uses against the Sicilian Defense (1.e4 c5) other than the most common plan of 2.Nf3 followed by 3.d4 cxd4 4.Nxd4 (the Open Sicilian). Some Anti-Sicilians include the Alapin Variation (2.c3), Moscow Variation (2.Nf3 d6 3.Bb5+), Rossolimo Variation (2.Nf3 Nc6 3.Bb5), Grand Prix Attack (2.Nc3 Nc6 3.f4 g6 4.Nf3 Bg7 and now 5.Bc4 or 5.Bb5), Closed Sicilian (2.Nc3 followed by g3 and Bg2), Smith-Morra Gambit (2.d4 cxd4 3.c3), and Wing Gambit (2.b4).

Arbiter

See International Arbiter.

Armageddon

A game which White must win to win the match, but which Black only needs to draw to win the match. White has more time than Black: the discrepancy can vary, but in FIDE World Championships, White has six minutes, while Black only has five. Typically used in playoff tie-breakers where shorter blitz games have not resolved the tie.

Artificial castling

Refers to a maneuver of several single moves by the king and a rook where they end up as if they had castled. Also known as "castling by hand".

Attack

An assault, either short-term (e.g., after 1.e4 Nf6, Black is attacking White's pawn on e4) or long-term, for example in the form of a sustained mating attack against the enemy king or a minority attack against the opponent's queenside pawn structure. See defence.

Attraction

If a player sacrifices minor or major pieces to expose the enemy king. For example, if the black king has castled and is on the g8-square, white may attempt to "attract" the king by using forcing moves such as Bxh7+, followed by Ng5+ etc.

Automaton

A self-operating chess-playing machine. Popular attractions in the 18th and 19th centuries, most of these devices were hoaxes under the control of a human player. The most famous chess-playing automaton was The Turk.

B

B

Symbol used for the bishop when recording chess moves in English.

Back rank

A player's first rank (the one on which the pieces stand in the initial array); White's back rank is Black's eighth rank, and vice versa.

Back-rank mate

A checkmate delivered by a rook or queen along a back rank in which the mated king is unable to move up the board because the king is blocked by friendly pieces (usually pawns) on the second rank. This is also sometimes referred to as a back-row mate.

Back-rank weakness

A situation in which a player is under threat of a back-rank mate and having no time/option to create an escape for the king must constantly watch and defend against that threat, e.g. keeping a rook on the back rank.

Backward pawn

A pawn that is behind the pawns of the same color on the adjacent files and that cannot be advanced with the support of another pawn.

Bad bishop

A bishop which is hemmed in by the player's own pawns.

Battery

An arrangement of two pieces in line with the enemy king on a rank, file, or diagonal so that if the middle piece moves a discovered check will be delivered. The term is also used in cases where moving the middle piece will uncover a threat along the opened line other than a check.

BCF

British Chess Federation, the former name of the English Chess Federation. See ECF.

BCM

An abbreviation for the British Chess Magazine.

BCO

An abbreviation sometimes used for the 1982 chess opening reference Batsford Chess Openings, by Raymond Keene and Garry Kasparov. The second edition (1989) is often called BCO-2. Cf. ECO and MCO.

Bind

A strong grip or stranglehold on a position that is difficult for the opponent to break. A bind is usually an advantage in space created by advanced pawns. The Maróczy Bind is a well-known example. See also Squeeze.

Bishop

see bishop

Bishops on opposite colors

A situation in which one side has only its light-squared bishop remaining while the other has only its dark-squared bishop remaining. In endgames, this often results in a draw if there are no other pieces (only pawns), even if one side has one or two pawns extra, since the bishops control different squares (see opposite-colored bishops endgame). In the middlegame, however, the presence of opposite-colored bishops imbalances the game and can lead to mating attacks, since each bishop attacks squares that cannot be covered by the other.

Bishop pair

In open positions, two bishops (on opposite colors) are considered to have an advantage over two knights or a knight and a bishop. (In closed positions knights may be more valuable than bishops.) The player with two bishops is said to have the bishop pair. Some evaluation systems count the bishop pair as being worth half of a pawn, see chess piece relative value#Alternate valuations.

Bishop pawn

A pawn on the bishop's file, i.e. the c-file or f-file.

Black

The designation for the player who moves second, even though the corresponding pieces, referred to as "the black pieces", are sometimes actually some other (usually dark) color. Similarly, the dark-colored squares on the chessboard are often referred to as "the black squares" even though they often are not literally black. See also White, First-move advantage in chess.

Blindfold chess

A form of chess in which one or both players are not allowed to see the board.

Blitz chess

A fast form of chess (Blitz being German for lightning) with a very short time limit, usually 3 or 5 minutes per player for the entire game. With the advent of electronic chess clocks, it is often the case that the time remaining is incremented by 1 or 2 seconds per move.

Blockade

A strategic placement of a minor piece directly in front of an enemy pawn, where it restrains the pawn's advance and gains shelter from attack. Blockading pieces are often overprotected.

Blunder

A very bad move, an oversight (indicated by "??" in notation).

Board

See chessboard.

Boden's Mate

Boden's Mate, named for Samuel Boden, is a checkmate pattern in chess in which the king, usually having castled queenside, is checkmated by two criss-crossing bishops. Immediately prior to delivering the mate, the winning side typically plays a queen sacrifice on c3 or c6 to set up the mating position.

Book draw

An endgame position known to be a draw with perfect play. The name reflects that traditionally the analysis has been found in the chess endgame literature, but in simplified positions (currently six pieces or fewer) computer analysis in an endgame tablebase can be used.

Book move

An opening move found in the standard reference books on opening theory. A game is said to be "in book" when both players are playing moves found in the opening references. A game is said to be "out of book" when the players have reached the end of the variations analyzed in the opening books or if one of the players deviates with a novelty (or a blunder).

Book win

An endgame position known to be a win with perfect play. The name reflects that traditionally the analysis has been found in the chess endgame literature, but in simplified positions (currently six pieces or fewer) computer analysis in an endgame tablebase can be used.

Break

A pawn advance or capture that opens a blocked position.

Breakthrough

Destruction of a seemingly strong defense, often by means of a sacrifice.

Brevity

(chiefly British) See Miniature.

Brilliancy

A spectacular and beautiful game of chess, generally featuring sacrificial attacks and unexpected moves. Brilliancies are not always required to feature sound play or the best moves by either side.

Brilliancy prize

A prize awarded at some tournaments for the best brilliancy played in the tournament.

Bronstein delay

A time control method with time delay, invented by David Bronstein. When it becomes a player's turn to move, the clock waits for the delay period before starting to subtract from the player's remaining time.

Bughouse chess

A chess variant played with teams of two or more.

Bullet chess

A form of chess in which each side has 1 minute to make all their moves.

Bust

Colloquial term for a refutation of an opening, or of previously published analysis. A famous example is Bobby Fischer's 1961 article "A Bust to the King's Gambit" in which he wrote, "In my opinion, the King's Gambit is busted. It loses by force." American Chess Quarterly, Summer 1961 (Vol. 1, No. 1), at 3, 4.

Bye

A tournament round in which a player does not have a game, usually because there are an odd number of players. A bye is normally scored as a win (1 point), although in some tournaments a player is permitted to choose to take a bye (usually in the first or last round) and score it as a draw (½ point).

C

Caïssa

The goddess of chess, occasionally invoked to indicate luck or good fortune: "Caïssa was with me".

Calculate

To carefully plan a series of moves while considering possible responses.

Candidate move

A move that seems good upon initial observation of the position, and that warrants further analysis.

Candidates Match

A knockout match in the Candidates Tournament.

Candidates Tournament

A tournament organised by the FIDE, the third and last qualifying cycle of the World Chess Championship. The participants are the top players of the interzonal tournament plus possibly other players selected on the basis of rating or performance in the previous candidates tournament. The top ranking player(s) qualify(ies) for the world championship.

Capped piece

A certain piece with which one player tries to deliver checkmate. When the capped piece is a pawn, it is called a pion coiffé (French for capped pawn). Playing with a capped piece is a handicap in chess.

Capture

Remove the opponent's piece or pawn from the board by taking it with one's own piece or pawn. Except in the case of an en passant capture, the capturing piece or pawn does so by occupying the same square that the captured piece or pawn occupied.

Castling

A special move involving both the king and one rook. Its purpose is generally to protect the king and develop the rook. Castling on the kingside is sometimes called castling short and castling on the queenside is called castling long; the difference is based on whether the rook moves a short distance (two squares) or a long distance (three squares).

Castling into it

A situation where one side castles in such a way that the king is in more danger at the destination than on the initial square, either immediately or because lines and diagonals can be more readily opened against it. Because beginners, in line with simplified traditional notions, often falsely assume castling to always improve protection of the king, pre-war grandmaster and leading figure of the hypermodern school Richard Reti therefore exhorted players to "castle because you must, not because you can".

Castling long

Castling queenside, notated 0-0-0.

Castling short

Castling kingside, notated 0-0.

Casual game

See friendly game.

Category tournament

The category of a tournament is a measure of its strength based on the average FIDE rating of the participants. The category is calculated by rounding up the number (average rating − 2250)/25. So each category covers a 25 point rating range, starting with Category 1 which spans ratings between 2251 and 2275. A Category 18 tournament has an average rating between 2676 and 2700.

CC

An abbreviation sometimes used for correspondence chess.

Centralization

Moving a piece or pieces toward the center of the board. In general, pieces are best placed in or near the center of the board because they control a large number of squares and are available for play on either flank as needed. Because of their limited mobility, knights in particular benefit from being centralized. There are several chess aphorisms referring to this principle: "A knight on the rim is dim" (or "grim" instead of "dim") and "A knight on the side cannot abide."

Centre/Center

The four squares in the middle of the board.

Central pawn

A pawn on the king's file or queen's file, i.e. on the d-file or e-file.

Cheapo

Slang for a primitive trap, often set in the hope of swindling a win or a draw from a lost position.

Check

An attack on the king. The attacked king is said to be in check.

Checkmate

A position in which a player's king is in check and the player has no legal move (i.e cannot move out of check). A player whose king is checkmated loses the game.

Chess960

A chess variant with a randomized positioning of non-pawn pieces to start the game.

Chessboard

This is the chequered board used in chess. It consists of 64 squares (eight rows and eight columns) arranged in two alternating colors (light and dark). Similar boards are also known as checkerboards.

Chess clock

A device made up of two adjacent clocks and buttons, keeping track of the total time each player takes for their moves. Immediately after moving, the player hits his button, which simultaneously stops his clock and starts his opponent's. The picture shown displays an analogue clock where the term 'flag fall' originates. Modern clocks are digital.

Classical

• An opening system geared towards forming a full pawn center. See also Hypermodern.

• A game using a longer time control such as 40/2; the opposite of fast chess categories such as rapid, blitz or bullet.

Clearance

Removal of pieces from a rank, file or diagonal so that a bishop, rook or queen is free to move along it. A related term is "clearing the diagonal": removing pieces from a diagonal so that an enemy bishop, usually a fianchettoed bishop, has no targets to attack.

Clock move

A timed game is played clock move if a move is completed only when the clock has been pressed. It is therefore possible to touch one piece, but then decide to move another piece. This way of playing is common in casual games, in favour of touch move.

Clock time

Time (consumed or remaining) on the chess clock, in a tournament game.

Closed game

• A position with few open lines (files or diagonals), generally characterized by interlocking pawn chains, cramped positions with few opportunities to exchange, and extensive maneuvering behind lines. Such a position may later become an Open game. See also Positional play.
• A chess opening that begins with the moves 1.d4 d5. See also Open game and Semi-open game.

Closed file

A file on which black and white both have a pawn.

Closed tournament

A tournament in which only invited or qualifying players may participate, as opposed to an open tournament. Also called an invitational tournament.

Coffeehouse

Adjective used to describe a move, player, or style of play characterized by risky, positionally dubious play that sets traps for the opponent. The name comes from the notion that one would expect to see such play in skittles games played in a coffeehouse or similar setting, particularly in games played for stakes and/or blitz chess. The Blackburne Shilling Gambit is a typical example of coffeehouse play.

Color

The white or black pieces. May also refer to a certain square, e.g. 1.e4 – White has played his/her pawn and is on the light-colored square.

Combination

A clever sequence of moves, often involving a sacrifice, to gain the advantage. The moves of the other player are usually forced, i.e. a combination does not give the opponent too many possible lines of continuation.

Compensation

An imbalanced equivalent return, for example sacrificing material for development or trading a bishop for three pawns.

Connected pawns

Refers to two or more pawns of the same color on adjacent files. See also isolated pawns.

Connected passed pawns

Passed pawns on adjacent files. These are considered to be unusually powerful (often worth a minor piece or rook if on the sixth rank or above and not properly blockaded) because they can advance together. Also see connected pawns.

Connected rooks

Two rooks of the same color on the same rank or file with no pawns or pieces between them. Connected rooks are usually desirable. Players often connect rooks on their own first rank or along an open file. cf. Doubled rooks.

Control of the centre/center

Having one or more pieces that attack any of the four centre squares; an important strategy, and one of the main aims of openings.

Cook

An unintended solution of a chess problem. The term may also be used more generally to refer to a refutation to published analysis.

Correspondence chess

This is chess played at a long time control by various forms of long-distance correspondence, usually through a correspondence chess server, through email or by the postal system. Typically, one move is transmitted in every correspondence.

Corresponding squares

Squares of reciprocal (or mutual) Zugzwang often found in king and pawn endgames. Also known as related squares.

Counterattack

An attack that responds to an attack by the other player.

Countergambit

A gambit offered by Black, for example the Greco Counter Gambit, usually called the Latvian Gambit today (1.e4 e5 2.Nf3 f5?!); the Albin Countergambit (1.d4 d5 2.c4 e5); and the Falkbeer Countergambit (1.e4 e5 2.f4 d5). An opening need not have "countergambit" in its name to be one; for instance, the Benko Gambit (1.d4 Nf6 2.c4 c5 3.d5 b5), Englund Gambit (1.d4 e5?), the Budapest Gambit (1.d4 Nf6 2.c4 e5), the Blackburne Shilling Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4?!) and many lines of the Two Knights Defense (e.g. 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 and now 4...Bc5!? (the Wilkes-Barre Variation or Traxler Counter-Attack), 4...Nxe4?!, 4...d5 5.exd5 Na5 6.Bb5+ c6 (the main line), 4...d5 5.exd5 Nd4 (the Fritz Variation), and 4...d5 5.exd5 b5 (the Ulvestad Variation)) are all examples of countergambits.

Counterplay

Active maneuvering by the player in an inferior or defensive position.

Cover

To protect a piece or control a square. For example, to checkmate a king on the side of the board, the five squares adjacent to the king must all be covered.

Cramped

A position with limited mobility.

Critical position

A position that is of key importance in determining the soundness of an opening variation. If one side can demonstrate an advantage in a critical position, the other side must either find an improvement or else abandon that variation as inferior.

Critical square

See Key square

Cross-check

A cross-check is a check played in reply to a check, especially when the original check is blocked by a piece which itself either delivers check or reveals a discovered check from another piece.

Crosstable

An arrangement of the results of every game in a tournament in tabular form. The names of the players run down the left side of the table in numbered rows. The names may be listed in order of results, alphabetically, or in pairing order, but results order is most common. The columns are also numbered, each one corresponding to the player in the same numbered row. Each table cell records the outcome of the game between the players on the intersecting row and column, using 1 for a win, 0 for a loss, and ½ for a draw. (In a double round-robin tournament each cell contains two entries, as each pair of players plays two games alternating white and black.) Every game is recorded twice, once from the perspective of each player. The diagonal cells that correspond to the player playing himself are marked with a * or other symbol as they are not used. For examples see Hastings 1895 chess tournament, Nottingham 1936 chess tournament, and AVRO tournament.

D

Dark squares

The 32 dark-coloured squares on the chessboard, such as a1 and h8. A dark square is always located at a player's left hand corner.

Dark-square bishop

One of the two bishops that moves on the dark squares, situated in c1 and f8 in the initial position.

Dead draw

A drawn position in which neither player has any realistic chance to win. A dead draw may refer to a position in which it is impossible for either player to win (such as insufficient material), or it may refer to a simple, lifeless position which would require a major blunder before either side would have a chance to win.

Decoy

This is a chess tactic used to lure a piece to an unfavourable square.

Defence

(1) A move or plan which tries to meet the opponent's attack; (2) an opening played by Black, for example the Scandinavian Defence, King's Indian Defense, English Defense, etc.

Deflect

The inverse of a decoy (see above). Whereas a decoy involves luring an enemy piece to a bad square, a deflection involves luring an enemy piece away from a good square; typically, away from a square on which it defends another piece or threat. Deflection is thus closely related to overloading (see below).

Demonstration board

A large standing chess board used to analyse a game or show a game in progress. Johann Löwenthal invented the demonstration board in 1857.

Descriptive notation

An old system of recording chess moves, used primarily in the English and Spanish speaking countries through the 1970s or 1980s. Now replaced by the standard algebraic notation.

Desperado

• A piece that seems determined to give itself up, typically either to bring about stalemate
• A piece to sell itself as dearly as possible in a situation where both sides have hanging pieces.

Develop

In the opening, moving a piece from its original square to make it more active. To redevelop a piece means to move it to a better square after it has already been developed.

Diagonal

A line of squares of the same colour touching corner to corner, along which a queen or bishop can move.

Discovered attack

An attack made by a queen, rook or bishop when another piece or pawn moves out of its way.

Discovered check

A discovered attack to the king. This occurs when a player moves a piece, resulting in another piece putting their opponents king in check.

Domination

A situation whereby capture of a piece is unavoidable despite it having wide freedom of movement. Usually occurs in chess problems.

Double attack

Two attacks made with one move: these attacks may be made by the same piece (in which case it is a fork); or by different pieces (a situation which may arise via a discovered attack in which the moved piece also makes a threat). The attacks may directly threaten opposing pieces, or may be threats of another kind: for instance, to capture the queen and deliver checkmate.

Double check

A check delivered by two pieces at the same time. A double check necessarily involves a discovered check.

Doubled pawns

A pair of pawns of the same color on the same file; generally considered a weakness due to their inability to defend each other.

Doubled rooks

A powerful position in which two of a player's rooks are placed on the same file or rank with no other chessmen between them. In this position, they defend each other while attacking both laterally and along the shared row. The position especially can be decisive when achieved during the endgame phase of play.

Draw

A game that ends without victory for either player. Most drawn games are draws by agreement. The other ways that a game can end in a draw are stalemate, threefold repetition, the fifty-move rule, and insufficient material. A position is said to be a draw (or a "drawn position" or "theoretical draw") if either player can, through correct play, eventually force the game into a position where the game must end in a draw, regardless of the moves made by the other player. A draw is usually scored as ½ point, although in some matches only wins are counted and draws are ignored.

Drawing line

An opening variation that commonly ends in a draw, for example 1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 4.Bb5 Nd4 5.Nxd4 exd4 6.e5 dxc3 7.exf6 Qxf6 8.dxc3 Qe5+ 9.Qe2 Qxe2+, a line in the Rubinstein Variation of the Four Knights Game. See Collection of drawing lines at chessgames.com. Often such a variation is played because one or both players are eager to draw the game.

Drawish

An adjective describing a position or game that is likely to end in a draw.

Draw odds

A type of chess handicap where one player (Black in an #Armageddon game) only has to draw in order to win the match.

Drawing weapon

An opening line that a player plays with the intent of drawing the game. This may or may not be a line commonly thought of as a drawing line. In high-level chess and correspondence chess, a player well-versed in opening theory may even use as a drawing weapon a sharp opening that has been analyzed to a drawn position in a number of lines, such as the Marshall Attack in the Ruy Lopez, and the Sveshnikov and Poisoned Pawn variations of the Sicilian Defense. One example of the successful employment of a drawing weapon was the 2000 World Chess Championship match between Garry Kasparov and Vladimir Kramnik. In that match, Kramnik used the Berlin Defense to the Ruy Lopez as a drawing weapon with great effect. Kramnik drew all four games with that opening, drew all the rest of his games as Black, and won two games as White, with no losses.

Duffer

A weak chess player, also referred to as a "fish", "patzer" or "woodpusher."

Dynamism

A style of play in which the activity of the pieces is favoured over more positional considerations, even to the point of accepting permanent structural or spatial weaknesses. Dynamism stemmed from the teachings of the 'Hypermodern movement' and challenged the dogma found in more classical teachings, such as those put forward by Wilhelm Steinitz and Siegbert Tarrasch.

E

ECF

The English Chess Federation (ECF) is the governing chess organisation in England and is one of the federations of the FIDE. It was known as the British Chess Federation (BCF) until 2005 when it was renamed.

ECO

The Encyclopaedia of Chess Openings, a standard and comprehensive chess opening reference. Also a classification system (ECO code) for chess openings that assigns an alphanumeric code from A00 to E99 to each opening.

Edge

An edge is a small but meaningful advantage in the position against one's opponent. It is often said White has an edge in the starting position, since he moves first (see First move advantage in chess).

Elo rating system

The Elo rating system is a method for calculating the relative skill levels of chess players, named after the Hungarian Arpad Elo. Since 1970 FIDE publishes quarterly an international chess rating list using the Elo system.

En passant

("in the act of passing"; derived from French) The rule that allows a pawn that has just advanced two squares to be captured by a pawn on the same rank and adjacent file. The pawn is therefore taken as if it had only moved one space. It is only possible to take en passant on the next move.

En prise

(from French; "in a position to be taken",^[1][2] often italicized) En prise describes a piece or pawn exposed to a material winning capture by the opponent. This is either a hanging piece, an undefended pawn, a piece attacked by a less valuable attacker, or a piece or pawn defended insufficiently. For instance, after 1.e4 Nf6 2.Nf3? leaves White's e-pawn en prise.

Endgame

The stage of the game when there are few pieces left on the board. The endgame follows the middlegame.

Endgame tablebase

A computerized database of endgames with up to seven pieces, providing perfect play for both players, and thus completely solving those endgames. (The six-piece endgames have been finished; some seven-piece endgames have been finished as of 2008.)

Epaulette mate

A checkmate position where the king is blocked on both sides by his own rooks.

Extended Position Description (EPD)

A Forsyth-Edwards Notation derivative format that contains the position on the chessboard, but not the game. It is primarily used to test chess engines.

Equalise/Equalize

To create a position where the players have equal chances of winning (referred to as "equality"). This may be either "static equality", where a draw is likely (for example, a balanced endgame) or even certain (for example, by perpetual check), or "dynamic equality", where White and Black have equal chances of winning the game. In opening theory, since White has the advantage of the first move, lines that equalize are relatively good for Black and bad for White.

Escape square

A square to which a piece can move, which allows it to escape attack. See also flight square and luft.

Exchange

• The capture of a pair of pieces, one white and the other black, usually of the same type (i.e rook for rook, knight for knight etc.), or of bishop for knight (two pieces that are considered almost equal in value).
• The exchange is used to refer to the advantage of a rook over a minor piece (knight or bishop). The player who captures a rook while losing a minor piece is said to have won the exchange, and the opponent is said to have lost the exchange. An exchange sacrifice is giving up a rook for a minor piece.

Exchange variation

This is a type of opening in which there is an early, voluntary exchange of pawns or pieces.

Exhibition

A contest of one or more games played for the purpose of public entertainment, as opposed to a match or tournament. An exhibition may pit two masters against each other, in which case chess clocks are normally used and the contest is quite serious. A simultaneous exhibition (or display) has one or more masters play many celebrity or amateur opponents at once, and is often not timed.

Expanded centre

The central sixteen squares on the board.

F

Family fork, family check

A knight fork that simultaneously attacks the enemy king (giving check), queen, and possibly other pieces.

Fast chess

A form of chess in which both sides are given less time to make their moves than under the normal tournament time controls. See also blitz chess.

FEN

Abbreviation for Forsyth-Edwards Notation, which is a standard notation for describing a particular board position of a chess game. The purpose of FEN notation is to provide all the necessary information to restart a game from a particular position.

Fianchetto

Refers to a bishop developed to the second square and the longest diagonal on the file of the adjacent knight (that is, b2 or g2 for white, b7 or g7 for black), or the process of developing a bishop to such a square. It usually occurs after moving the pawn on that file ahead one square (or perhaps two). The Italian word is actually a noun ("in fianchetto") and not a verb.

FIDE

The World Chess Federation (Fédération Internationale des Échecs), the primary international chess organizing and governing body. The abbreviated name FIDE is nearly always used in place of the full name in French.

FIDE Master (FM)

A chess title ranking below International Master.

Fifty-move rule

A draw may be claimed if no capture or pawn move has occurred in the last fifty moves by either side.

File

A column of the chessboard. A specific file can be named either using its position in algebraic notation, a–h, or by using its position in descriptive notation. For example, the f-file or the king bishop file comprises the squares f1–f8 (or KB1–KB8 in descriptive chess notation).

First board

See top board.

First-move advantage

The slight (by most accounts) advantage that White has by virtue of moving first.

Fischer delay

A time control method with time delay, invented by Robert Fischer. When it becomes a player's turn to move, the delay is added to the player's remaining time.

Fischer Random

see Chess960

Fish

A weak chess player, also referred to as a "duffer", "patzer" or "woodpusher".

Flag

Part of an analogue chess clock (usually red) which indicates when the minute hand passes the hour. To flag someone means winning the game on the basis of the opponent exceeding the time control.

Flank

The queenside a, b, and c-files, or the kingside f, g, and h-files, also called wing; distinguished from the center d and e-files.

Flank opening

This a chess opening played by White and typified by play on one or both flanks.

Flight square

A square to which a piece can move, which allows it to escape attack. See also escape square and luft.

FM

Abbreviation for the FIDE Master title.

Focal point

The square upon which a player focuses an attack, e.g. by repeatedly attacking that square or sacrificing a piece there. For example, in an attack upon an uncastled king, Black's f7 square (or White's f2 square) is a common focal point. Examples of attacks on the focal point f7 include the Fried Liver Attack (initiated by a knight sacrifice on f7) and the primitive Scholar's Mate (ending with checkmate on f7).

Fool's mate

The shortest possible chess game ending in mate: 1. f3 e5 2. g4 Qh4# (or minor variations on this).

Forced move

A move which is the only one which does not result in a serious disadvantage for the moving player. "Forced" can also be used to describe a sequence of moves for which the player has no viable alternative, e.g. "the forced win of a piece" or "a forced checkmate". In these cases the player cannot avoid the loss of a piece or checkmate, respectively.

Forfeit

Refers to losing the game by absence or by exceeding the time control (forfeit on time).

Fork

When one piece, generally a knight or pawn, simultaneously attacks two (or more) of the opponent's pieces, often specifically called a knight fork when the attacker is a knight. Some sources state that only a knight can give a fork and that the term double attack is correct when another piece is involved, but this is by no means a universal usage.

Fortress

A fortress is a position that, if obtained by the weaker side, will prevent the opposing side from penetration, this generally resulting in a draw (which the weaker side is seeking).

Friendly game

A game that is not played as part of a match, tournament, or exhibition. Often the game is not timed, but if a chess clock is used rapid time-controls are common. The term refers only to the circumstances in which the game is played, not the relationship between the players or the intensity of the competition. Also called a casual game.

G

Gambit

A sacrifice (usually of a pawn) used to gain an early advantage of space and /or time in the opening.

Game score

The record of a game in some form of notation. In over-the-board tournaments, the gamescore is recorded on a score sheet.

GM

abbreviation for Grandmaster.

Good bishop

A bishop which has high mobility, typically because the player's pawns are on squares of color opposite to that of the bishop. (See #Bad bishop.)

Grandmaster

The highest title a chess player can attain (besides World Champion). When used precisely, it is the title awarded by FIDE starting in 1950, but it can be used to describe someone of comparable ability. The term International Grandmaster or IGM would refer only to the FIDE title.

Grandmaster draw

A game in which the players quickly agree to a draw after making little or no effort to win. This may be a very boring game, e.g. 1.d4 d5 2.c4 c6 3.cxd5 cxd5 4.Nc3 Nf6 5.Nf3 Nc6 6.Bf4 Bf5 7.e3 e6 Draw Agreed, or a superficially exciting game played with a variation the players know leads to a draw, e.g. 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.0-0 Bg4 6.h3 h5 7.c3 Qd3 8.hxg4 hxg4 9.Nxe5 Bd6 (a pseudo-sacrifice of Black's queen) 10.Nxd3 Bh2+ 11.Kh1 Bd6+ and Black draws by perpetual check. Although originally used to refer to such games between grandmasters, the term is now used colloquially to refer to any such game.

Greek gift sacrifice

Also known as the classical bishop sacrifice, it is a typical sacrifice of a bishop by White playing Bxh7+ or Black playing Bxh2+ against a castled king to initiate a mating attack.

H

Half-open file

A file on which only one player has no pawns.

Handicap

See Odds.

Hanging

Unprotected and exposed to capture. It is not the same as en prise since a piece en prise may be protected. To "hang a piece" is to lose it by failing to move or protect it.

Hanging pawns

Two friendly pawns abreast without friendly pawns on adjacent files. Hanging pawns can be either a strength (usually because they can advance) or a weakness (because they cannot be defended by pawns) depending on circumstances.

Harrwitz bishops

A player's light-squared and dark-squared bishops placed so that they occupy adjacent diagonals; named for the mid-19th century master Daniel Harrwitz. For example, White has Harrwitz bishops in the Danish Gambit after 1.e4 e5 2.d4 exd4 3.c3 dxc3 4.Bc4 cxb2 5.Bxb2. Harrwitz bishops can be a potent attacking force in the middlegame. Also called raking bishops.

Heavy piece

A queen or rook, also known as a major piece.

Hole

A square that a player does not, and cannot in future, control with a friendly pawn. The definition is somewhat subjective: the square must have some positional significance for the opponent to be considered a hole – squares on the first and second ranks are not holes. On the other hand a square is a hole even if it can be controlled in the future with a pawn that has made a capture. An example of the hole is the square e4 in the Stonewall Attack.

Home rank

Rank one for White; rank eight for Black. See back rank.

Hypermodern

An opening system geared towards controlling the center with distant pieces as opposed to occupying it with pawns. See also Classical.

I

ICCA

See ICCF.

ICCF

The international Correspondence Chess Federation, founded in 1951 to replace the International Correspondence Chess Association (ICCA).

ICU

Irish Chess Union [1] publishes ICJ Irish Chess Journal

IGM

An abbreviation for the older term International Grandmaster. The modern usage is Grandmaster (GM).

Illegal move

A move that is not permitted by the rules of chess. An illegal move discovered during the course of a game is to be corrected.

Illegal position

• A position in a game that is a consequence of an illegal move or an incorrect starting position.
• In chess problems, an illegal position is one that is impossible to reach in a game by any sequence of legal moves.

IM

Abbreviation for the International Master title.

Inactive

See passive.

Increment

An increment refers to the amount of time added to each player's time before each move. For instance rapid chess might be played with "25 minutes plus 10 second per move increment", meaning that each player starts with 25 minutes on their clock, and this increments by 10 seconds after (or before) each move, usually using the Fischer Delay method. See Time control#Compensation (delay methods).

Indian bishop

A fianchettoed bishop, characteristic of the Indian defences, the King's Indian and the Queen's Indian.

Indian defence

A chess opening that begins 1.d4 Nf6. Originally used to describe queen's pawn defences involving the fianchetto of one or both Black bishops, it is now used to describe all Black defences after 1.d4 Nf6 that do not transpose into the Queen's Gambit.

Initiative

The advantage that a player who is making threats has over the player who must respond to them. The attacking player is said to "have the initiative". s/he can often turn the play as s/he wills. The initiative often results from an advantage in time and/or space. The notion of the initiative was used by Steinitz (e.g. The Sixth American Chess Congress) and by Capablanca in his Chess Fundamentals (Chapter 4).

Insufficient material

An endgame scenario in which all pawns have been captured, and one side has only its king remaining while the other is down to just a king, a king plus one knight, a king plus one bishop, or indeed a king plus any number of bishops on the same colour as each other (up to nine), as is possible via underpromotion. A king and bishop versus a king and bishop with the bishops on the same color is also a draw. The position is a draw because it is impossible for the dominant side to deliver checkmate regardless of play. Situations where checkmate is possible only if the inferior side blunders are covered by the fifty-move rule. (See Draw (chess)#Draws in all games.)

Interference

This happens when the line between an attacked piece and its defender is interrupted by sacrificially interposing a piece.

Intermediate move

See zwischenzug.

International Arbiter

A tournament official who arbitrates disputes and performs other duties such as keeping the score when players are under time pressure.

International Grandmaster (IGM)

The original name of the FIDE title now simply called Grandmaster (GM).

International Master (IM)

A chess title that ranks below Grandmaster but above FIDE Master.

Internet chess server

This is an external server that provides the facility to play, discuss, and view chess over the internet, also abbreviated ICS.

Interpose

To move a piece between an attacking piece and its target, blocking the line of attack. Interposing a piece is one of the three possible responses to a check, the others being to move the king or capture the attacking piece.

Interzonal Tournament

A tournament organised by the FIDE, the second qualifying cycle of the World Chess Championship. The participants are selected from the top players of the zonal tournaments. The top ranking players qualify for the candidates tournament.

IQP

An abbreviation for Isolated Queen Pawn. See also isolani.

Irregular opening

Irregular openings are chess openings with an unusual first move from White. These openings are all categorized under the ECO code A00.

Isolani

refers to a d-Pawn with no Pawns of the same color on the adjacent c- and e-files, and is a synonym for 'Isolated Queen's Pawn'. The term was coined by Nimzovitch, who considered the isolani as a weapon of attack in the middle game but an endgame weakness; he considered the problem of hanging pawns to be related.

Isolated pawn

A pawn with no pawn of the same color on an adjacent file.

Italian bishop

A White bishop developed to the c4 square or a Black bishop developed to c5. This development is characteristic of the Italian Game, 1.e4 e5 2.Nf3 Nc6 3.Bc4, particularly the Giuoco Piano, 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5, where both players have Italian bishops. Likewise, "Italian" may be used as an adjective denoting an opening where one or both players has an Italian bishop, such as after 1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 4.Bc4, the Italian Four Knights Game.

J

J'adoube

(from French) "I adjust". A player says "J'adoube" as the international signal that he intends to adjust the position of a piece on the board without being subject to the touched piece rule.

K

K

Symbol used for the king when recording chess moves in English.

Keizer system

A pairing system where a players plays an opponent who is close in the ranking. Named after the Dutch inventor of the system, and useful when the number of participants exceeds the number of playing rounds.

Also see Swiss tournament and Round-robin tournament.

Key square

1. An important square.
2. (Pawn endings) A square whose occupation by one side's king guarantees the achievement of a certain goal, such as the promotion of a pawn or the win of a pawn.

KGA

The King's Gambit Accepted chess opening.

KGD

The King's Gambit Declined chess opening.

KIA

the King's Indian Attack chess opening.

Kibitz

As a spectator, making comments on a chess game that can be heard by the players. Kibitzing on a serious game while it is in progress (rather than during a post-mortem) is a serious breach of chess etiquette.

Kick

Attacking a piece, typically by a pawn, so that it will move.

KID

The King's Indian Defence chess opening.

King

see king

King Bishop

The bishop that was on the king-side at the start of the game. The terms King Knight and King Rook are also used. Sometimes abbreviated KB, KN, and KR respectively.

King hunt

A sustained attack on the enemy king that results in the king being driven a far distance from its initial position, typically resulting in its checkmate. Some of the most famous games featuring king hunts are Edward Lasker-Thomas, Polugaevsky-Nezhmetdinov, and Kasparov-Topalov.

King pawn

A pawn on the king's file, i.e. the e-file. Sometimes abbreviated KP. Also King Bishop Pawn (KBP), King Knight Pawn (KNP), and King Rook Pawn (KRP) for a pawn on the f, g, or h-file respectively.

Kingside

The side of the board where the kings are at the start of the game (the e through h files), as opposed to the queenside.

Knight

see knight

Knight pawn

A pawn on the knight's file, i.e. the b-file or g-file.

Knight's tour

A mathematical treatment of a knight "touring" the board.

Knockout tournament

A tournament conducted as a series of matches in which the winner of each match advances to the next round and the loser is eliminated. Well known chess tournaments held in the knockout format include London 1851 and the 2007 Chess World Cup. Cf. #Round-robin tournament and Swiss tournament.

Kotov syndrome

This phenomenon, first described by Alexander Kotov, can occur when a player does not find a good plan after thinking long and hard on a position. The player, under time pressure, then suddenly decides to make a move, often a terrible one which was not analysed properly.

Kt

The symbol sometimes used for the knight when recording chess moves in descriptive notation, mainly in older literature. An N is used instead in algebraic notation and in later descriptive notation to avoid confusion with K, the symbol for the king.

L

Laws of Chess

The rules of chess.

Lightning chess

A form of chess with an extremely short time limit, usually 1 or 2 minutes per player for the entire game.

Light squares

the 32 light-coloured squares on the chessboard, such as h1 and a8.

Light-square bishop

One of the two bishops moving on the light squares, situated on f1 or c8 in the initial position.

Line

• A sequence of moves, usually in the opening or in analyzing a position.
• An open path for a piece (queen, rook, or bishop) to move or control squares.

Liquidation

See simplification.

Long diagonal

One of the two diagonals with eight squares (a1–h8 or h1–a8).

Long-range piece

A bishop, rook, or queen.

Loss

A loss for one of the two players, which may occur due to that player being checkmated by the other player, resigning, exceeding the time control, or being forfeited by the tournament director. Chess being a zero-sum game, this results in a win for the other player, except in the very rare circumstance where the tournament director forfeits both players, for example for cheating or both players exceeding the time control (the latter does not normally result in a double forfeit today).

Lucena position

A well-known rook and pawn versus rook endgame position in which the player with the extra pawn can force a win.

Luft

(from the German for air) Space made for a castled king to give it a flight square to prevent a back rank mate. Usually luft is made by moving a pawn on the second rank in front of the king.

M

Main line

The principal, most important, or most often played variation of an opening or piece of analysis. For example, 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Nc6 8.d5 Ne7 is often referred to as the main line of the King's Indian Defence.

Major piece

A queen or rook, also known as a heavy piece.

Majority

A larger numbers of pawns on one flank opposed by a smaller number of the opponent's; often a player with a majority on one flank has a minority on the other.

Man

A piece or a pawn, when the term piece is used as exclusive of pawns. Note that the queen is also a man.

Maróczy Bind

A bind on the light squares in the center, particularly d5, obtained by White by placing pawns on c4 and e4. Named for Géza Maróczy, it originally referred to formations arising in some variations of the Sicilian Defence, but the name is now also applied to similar setups in the English Opening and the Queen's Indian Defence. It was once greatly feared by Black but means of countering it have been developed since the 1980s and earlier.

Match

A competition between two individuals or two teams. A match may be the entire competition, or it may be a round in a knockout tournament or team tournament. Unlike in some sports where the word match is sometimes used to describe a single game, a chess match always consists of at least two games (and often many more).

Mate

Short for checkmate.

Material

All of a player's pieces and pawns on the board. The player with pieces and pawns of greater value is said to have a "material advantage". When a player gains a material advantage they are also said to be "winning material". (See Chess piece relative value.)

Mating attack

An attack aimed at checkmating the enemy king.

MCO

Modern Chess Openings, a popular chess opening reference. Often the edition is also given, as in MCO-14, the 14th edition. Cf. ECO.

Middlegame

The part of a chess game that follows the opening and comes before the endgame, beginning after the pieces are developed in the opening. This is usually roughly moves 20 through 40.

Miniature

A short game (usually no more than 20 to 25 moves), for example 1.e3 e5 2.Qf3 d5 3.Nc3 e4 4.Qf4?? Bd6! and White resigned in NN-Künzel because his queen is trapped. However, a significant minority of authors include games up to 30 moves. John Nunn, 101 Brilliant Chess Miniatures, Gambit Publications, 1999, p. 6. ISBN 1-901983-16-1. Usually only decisive games (not draws) are considered miniatures. Ideally, a miniature should not be spoiled by an obvious blunder by the losing side. A miniature may also qualify as a brilliancy. The Opera game is a famous example. Sometimes called a brevity (chiefly British).

Minor exchange

The exchange of a bishop for a knight.

Minor piece

A bishop or knight.

Minority attack

An advance of pawns on the side of the board where one has fewer pawns than the opponent, usually carried out to provoke a weakness.

Mobility

The ability of a piece, or of a player's pieces collectively, to move around the board. (In computer chess this is often measured by the number of legal moves available.) Effectively means much the same as Space.

Mobile pawn center

Pawns on central squares able to advance without becoming weak.

Move

A full move is a turn by both players, White and Black. A turn by either White or Black is a half-move, or one ply.

Move order

The sequence of moves one chooses to play an opening or execute a plan. Different move orders often have different advantages and disadvantages. For example, 1.d4 Nf6 2.Nf3 avoids the Budapest Gambit (2.c4 e5!?), but makes it impossible for White to play the Sämisch Variation (2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f3) or Four Pawns Attack (5.f4) against the King's Indian Defence, and to transpose to certain lines of the Nimzo-Indian Defence and Queen's Gambit Declined, Exchange Variation where the knight goes to e2 instead of f3. (See transposition.)

Mysterious rook move

Following Nimzovich's idea, a move with a Rook that seems to have no threat or purpose, but which actually discourages the opponent from a certain type of action (prophylaxis), or sets up a very deep, well-concealed plan.

N

N

Symbol used for the knight when recording chess moves in English.

NCO

Abbreviation sometimes used for the chess opening reference Nunn's Chess Openings. Cf. ECO and MCO.

NN or N.N.

Used in a game score in place of a player whose name is not known. The origin of this usage is uncertain. It may be an abbreviation of the Latin nomina (names), or it may be short for the Latin phrase nomen nescio, "names unknown" (literally "I do not know the name"). See also Amateur.

Norm

A performance at a chess tournament that indicates a player is ready to receive a title, or the level of performance needed. In addition to other requirements, a certain number of norms is generally required to earn a title. See Grandmaster and International Master.

Novelty

A new move in the opening. Sometimes called a "theoretical novelty" or "TN."

O

Odds

This refers to the stronger player giving the weaker player some sort of advantage, such as in material, extra moves, time on the clock, or some combination thereof. Since the advent of the chess clock, time odds have become more common than material odds. The stronger player will begin the game with only one or two minutes on the clock, while the weaker player is given five or more minutes on the clock.

Offhand game

See skittles.

Olympiad

An international team chess tournament organized biennially by FIDE. Each team represents a FIDE member country.

O-O

This term is a common abbreviation for kingside castling.

O-O-O

This term is a common abbreviation for queenside castling.

Open file

A file on which there are no pawns. A file on which only one player has no pawns is said to be half-open.

Open game

• A game in which exchanges have opened files and diagonals, as opposed to a closed game.
• A chess opening that begins with the moves 1.e4 e5 (which is also called a Double King Pawn opening). See also closed game and semi-open game.

Open tournament

A tournament where anyone can enter, regardless of rating or invitation. (Compare to closed tournament.)

Opening

The beginning moves of the game, roughly the first 10-20 moves. In the opening players set up their pawn structures, develop their pieces, and typically castle. The opening precedes the middlegame.

Opening preparation

Home study and analysis of openings and defenses that one expects to play, or meet, in later tournament or match games. In high-level play, an important part of this is the search for theoretical novelties that improve upon previous play or previously published analysis.

Opening repertoire

The set of openings played by a particular player. The breadth of different players' repertoires varies from very narrow to very broad. For example, a player who always opens with 1.e4; always meets 1.e4 with the Sicilian Defence, and the Najdorf Variation of it if allowed; and always meets 1.d4, 1.c4, or 1.Nf3 with 1...f5, intending to play the Dutch Defence, has a very narrow opening repertoire. Bent Larsen, who opened at various times with 1.e4, 1.d4, 1.c4, 1.f4, 1.Nf3, 1.b3, and 1.g3, and played a large number of different defenses as Black, had a very broad opening repertoire.

Opening system

An opening, such as the Colle System or Hippopotamus Defence, that is defined by one player's moves, which can be played regardless of the moves of the opponent.

Optimal play

Optimal play is when both sides make their best move at each turn, or one of equally good alternatives. One side tries to win as quickly as possible while the other side tries to delay it as long as possible, or optimal play may result in a draw.

Opposite color bishops

See Bishops on opposite colors.

Opposition

A situation in which two kings stand on the same rank, file or diagonal with one empty square between them. The player to move may be forced to move the king to a less advantageous square. Opposition is a particularly important concept in endgames.

Outside passed pawn

A passed pawn that is near the edge of the board and far away from other pawns. In the endgame, such a pawn often constitutes a strong advantage for its owner.

Outpost

Main article: Outpost

An outpost is a square protected by a pawn that is in or near the enemy's stronghold. Outposts are a favourable position from which to launch an attack, particularly using a knight.

Overextended

A position where a player has moved a piece or group of pieces (usually pawns) away from the rest in such a way that they are too difficult to defend.

Overloaded

A piece that has too many defensive duties. An overloaded piece can sometimes be deflected, or required to abandon one of its defensive duties.

Overprotection

Overprotection in chess is the strategy of protecting a pawn or specific square of the chessboard more than is immediately necessary. This serves to dissuade the opponent from attacking that specific point and provides greater freedom of movement for the pieces protecting that square. This can cause an opponent to pursue a faulty plan or no plan at all. Aron Nimzowitsch was one of the foremost proponents of overprotection.

Over-the-board (OTB)

A game is said to be played over-the-board if opponents play the game face-to-face as opposed to online chess or correspondence chess.

Overworked

Another term for Overloaded.

P

Pairing

The assignment of opponents in a tournament. Pairing is made more difficult in chess because of the need to try to give each player an equal number of games playing white and black and to try to not assign a player the same color in too many consecutive games. The most common pairing methods used in chess tournaments are round-robin and the Swiss system.

Passive

A piece that is able to move to or control relatively few squares, also referred to as an inactive piece. See active.

Passive sacrifice

When a piece is sacrificed by moving a different piece, leaving the sacrificed piece under attack.

Passed pawn

A pawn that has no pawn of the opposite color on its file or on any adjacent files on its way to queening.

Passer

A passed pawn.

Patzer

A weak chess player, also referred to as a "fish", "woodpusher", "duffer", or "bunny." (German: patzen, to bungle.)

Pawn

see pawn

Pawn and move

A type of odds game, common in the 18th and 19th centuries, in which the superior player plays Black and begins the game with one of his pawns, usually the king bishop pawn, removed from the board.

Pawn centre

A player has a pawn centre when he has several pawns in the centre. By extension, pawns on the squares adjacent to the centre may also be considered as part of the pawn centre. Having an ample pawn centre as the one on the diagram at right was considered a huge advantage until the hypermodernist school nuanced this judgment. See King's Indian Defence, Four Pawns Attack for an example of an opening leading to an extended pawn centre.

Pawn chain

A locked diagonal formation of pawns, each one supported by a friendly pawn diagonally behind and blocked by an enemy pawn directly ahead. Nimzowitsch considered pawn chains extensively, and recommended attacking the enemy pawn chain at its base. See pawn structure.

Pawn island

A group of pawns of one color on consecutive files with no other pawns of the same color on any adjacent files. A pawn island consisting of one pawn is called an isolated pawn.

Pawn storm

An attacking technique where a group of pawns on one wing is advanced to break up the defence.

Pawn structure

The placement of the pawns is known as the pawn structure. As pawns are the least mobile of the pieces and the only pieces unable to move backwards, the position of the pawns greatly influences the character of the game.

PCA

The Professional Chess Association (PCA) was a rival organisation to FIDE, the international chess organization. The PCA was created in 1993 by Garry Kasparov and Nigel Short for the marketing and organization of their chess world championship. The PCA lost its main sponsor, Intel, in 1996 and folded soon after.

Performance rating

A number reflecting the approximate rating level at which a player performed in a particular tournament or match. It is often calculated by adding together the player's performances in each individual game, using the opponent's rating for a draw, adding 400 points to the opponent's rating for a win, and subtracting 400 points from the opponent's rating for a loss, then dividing by the total number of games. For example, a player who beat a 2400-rated player, lost to a 2600, drew a 2500, and beat a 2300, would have a performance rating of 2550 (2800 + 2200 + 2500 + 2700, divided by four).

Perpetual check

A draw forced by one player putting the opponent's king in a potentially endless series of checks.

Philidor position

Usually refers to an important chess endgame which illustrates a drawing technique when the defender has a king and rook versus a king, rook, and pawn. It is also known as the third rank defence, because of the importance of the rook on the third rank cutting off the opposing king. It was analyzed by Philidor in 1777. (Also see rook and pawn versus rook endgame.)

Piece

This term can mean either any chess piece including pawns (as in the touched piece rule), or a minor piece (as in "I hung a piece"), depending on context. It can also mean a major or minor piece, as in "White needs to get some pieces to the kingside".

Pin

When a piece can not move (either legally or advisedly) because doing so would expose a valuable piece, usually the king or queen, to attack. Pins against the king are called absolute because it is then illegal to move the pinned piece.

Plan

A strategy used by a chess player to make optimal use of his advantages in a specific position while minimizing the impact of his positional disadvantages.

Playable

Said of an opening or move that gives the person playing it a tenable position, e.g. "Petroff's Defense is playable." or (after 1.e4 e5 2.Bc4 Nf6 3.Nc3 Nxe4 4.Nxe4) "4...d5 is the only playable move."

Ply

Term mainly used in computer chess to denote one play of either white or black. Thus equal to half a move.

Poisoned Pawn

An unprotected pawn which, if captured, causes positional problems or material loss. It is also a variation of the Najdorf Variation of the Sicilian Defence, where some players call White's pawn on b2 a poisoned pawn since it is dangerous for Black to capture it.

Portable Game Notation (PGN)

This is a popular computer-processible ASCII format for recording chess games (both the moves and related data).

Positional play

Play dominated more by long-term maneuvering for advantage than by short-term attacks and threats, and requiring judgment more than extensive calculation of variations, as distinguished from tactics.

Positional player

A player who specializes in positional play, as distinguished from a tactician.

Post-mortem

Analysis of a game after it has concluded, typically conducted by one or both players and sometimes spectators (kibitzers) as well.

Prepared variation

A well-analyzed novelty in the opening which is not published but first used against an opponent in competitive play.

Promotion

Advancing a pawn to the eighth rank, converting it to a queen, rook, bishop or knight. Promotion to a piece other than a queen is called underpromotion.

Prophylaxis

(adjectival form: prophylactic)

• a move that frustrates an opponent's plan or tactic;
• a strategy in which a player frustrates tactics initiated by the opponent until a mistake is made.

Prophylactic techniques include the blockade, overprotection, and the mysterious rook move.

Protected passed pawn

A passed pawn that is supported by another pawn.

Pseudo-sacrifice

See Sham sacrifice.

Push

To move a pawn forward.

Q

Q

Symbol used for the queen when recording chess moves in English.

QGA

The Queen's Gambit Accepted chess opening.

QGD

The Queen's Gambit Declined chess opening.

QID

The Queen's Indian Defence chess opening.

Quad

A round-robin style tournament between four players, where each participant plays every other participant once.

Queen

Also used as a verb for the act of promoting to a Queen, e.g. "... to queen the pawn".

Queen Bishop

The bishop that was on the queenside at the start of the game. The terms Queen Knight and Queen Rook are also used. Sometimes abbreviated QB, QN, and QR respectively.

Queen pawn

A pawn on the queen's file, i.e. the d-file. Sometimes abbreviated QP. Also Queen Rook Pawn (QRP), Queen Knight Pawn (QNP), and Queen Bishop Pawn (QBP) for pawns on the a, b, and c-files respectively.

Queening

Promotion to a queen. Also called #Promotion. Rarely used to indicate promotion to a knight, rook, or bishop as well (underpromotion).

Queenside

The side of the board where the queens are at the start of the game (the a through d files), as opposed to the kingside.

Quickplay finish

Same as "Sudden Death".

Quiet move

A move which does not attack or capture an enemy piece.

R

R

Symbol used for the rook when recording chess moves in English.

Raking bishops

Another term for Harrwitz bishops.

Rank

A row of the chessboard. Specific ranks are referred to by number, first rank, second rank, …, eighth rank. Unlike the case with files, rank names are always given from the point of view of each individual player, with the first rank being the home row of the king and other pieces. White's first rank is Black's eighth rank (row 1) and White's eighth is Black's first (row 8), White's second rank is Black's seventh rank (row 2) and White's seventh is Black's second (row 7), and so on.

Rapid chess

A form of chess with reduced time limit, usually 30 minutes per player.

Refute

Demonstrate that a strategy, move, or opening is not as good as previously thought (often, that it leads to a loss), or that previously published analysis is unsound. A refutation is sometimes colloquially referred to as a "bust". A refutation in the context of chess problems or endgame studies is often called a "cook".

Related squares

See corresponding squares.

Relative pin

A pin, where it is legal to move the pinned piece. See absolute pin.

Reserve tempo

A move a player has available, though superfluous to the game position, may have great effect by virtue of passing the move turn to one's opponent. See Reserve tempo.

Resign

To concede loss of the game. A resignation is usually indicated by stopping the clocks, and sometimes by offering a handshake or saying "I resign". The traditional way to resign is by tipping over one's king, but this is rarely done nowadays.^[3] In published games, a player's resignation is often indicated by "1–0" (Black resigns) or "0–1" (White resigns); these may also indicate that the game was decided for some other reason, usually one side exceeding the time control. In master and serious amateur play, it is much more common for a game to be resigned than for it to end with checkmate, because players can foresee checkmate well in advance. (See rules of chess#Resigning.) "A good player knows the right moment to resign." – Proverb

Romantic chess

Romantic chess was the style of chess prevalent in the 19th century. It is characterized by bold attacks and sacrifices.

Rook

see rook

Rook lift

A maneuver that places a rook in front of its own pawns, often on the third or fourth rank. This can allow the rook to treat a half-open file as if it were an open file, or a closed file as if it were half-open.

Rook pawn

A pawn on the rook's file, i.e. the a-file or h-file.

Round-robin tournament

This is a tournament in which each participant plays every other participant an equal number of times. In a double round-robin tournament the participants play each other exactly twice, once with white and once with black. An example of the former is the Hastings 1895 chess tournament, an example of the latter is the Piatigorsky Cup. This type of tournament is commonly used if the number of participants is relatively small. See also Swiss system tournament.

Royal fork

A fork between king and queen.

Royal pieces

Refers to the kings and queens.

S

S

Alternate notation for the knight piece. Used rather than the K, which is for King. From the German "Springer"

Sac

Short for sacrifice, usually used to describe a sacrifice for a mating attack.

Sacrifice

When one player voluntarily gives up material in return for an advantage such as space, development, or an attack. A sacrifice in the opening is called a gambit.

Sans voir

(from the French) See Blindfold chess.

Scholar's Mate

A four-move checkmate (common among novices) in which White plays 1. e4, follows with Qh5 (or Qf3) and Bc4, and finishes with 4. Qxf7#.

Score

A record of the moves of a particular game, usually expressed in algebraic notation.

Score sheet

The sheet of paper used to record a game in process. During formal games, it is usual for both players to record the game using a score sheet.

Sealed move

Lengthy OTB games can be adjourned. To prevent unfair advantage, the players can agree on the next move being secretly recorded in a sealed envelope. Upon resumption, the arbiter makes the sealed move and the game continues. See also Adjournment.

Second

An assistant, often hired to help a player in preparation for and during a major match or tournament. The second assists the players in areas such as opening preparation.^[4] The second also assisted with adjournment analysis, before the practice of adjournments was abandoned in the 1990s.

Seesaw

See Windmill.

Semi-Open Game

A chess opening that begins with White playing 1.e4 and Black replying with a move other than 1...e5. Also called Half-open or Asymmetrical King Pawn openings. See also open game and closed game.

Semi-Closed Game

A chess opening that begins with White playing 1.d4 and Black replying with a move other than 1...d5. See also open game and closed game.

Sham sacrifice

An offer of material which is made at no risk, as acceptance would lead to the gain of equal or greater material or checkmate. This is in contrast to a true sacrifice in which the compensation is less tangible. Also called a pseudo-sacrifice.

Sharp

Risky, double-edged, highly tactical. Sharp can be used to describe moves, maneuvers, positions, and styles of play.

Simplification

A strategy of exchanging pieces of equal value. Simplification can be used defensively to reduce the size of an attacking force. It can also be used by a player with an advantage to amplify that advantage or reduce the opponent's counterplay. Simplification is also used as an attempt to obtain a draw, or as an attempt to gain an advantage by players who are strong in endgame play with simplified positions. Also liquidation and trading.

Simultaneous chess

A form of chess in which one (usually expert) player plays against several (usually novice) players simultaneously. Is often an exhibition.

Skewer

An attack to a valuable piece, compelling it to move to avoid capture and thus exposing a less valuable piece which can then be taken.

Skittles

A casual or "pick-up" game, usually played without a chess clock. At chess tournaments, a skittles room is where one goes to play for fun while waiting for the next formal game.

Smothered mate

A checkmate delivered by a knight in which the mated king is unable to move owing to it being surrounded (or smothered) by its own pieces. This could occur, for example, after 1.e4 Nc6 2.Ne2 Ne5, and now either 3.c3?? Nd3# or 3.g3?? Nf3#.

Solid

An adjective used to describe a move, opening, or manner of play that is characterized by minimal risk-taking and emphasis on quiet positional play rather than wild tactics.

Sound

Correct. A sound sacrifice has sufficient compensation, a sound opening or variation has no known refutation, and a sound composition has no cooks.

Space

The squares controlled by a player. A player controlling more squares than the other is said to have a spatial advantage. Effectively means much the same as mobility.

Spanish bishop

A White king bishop developed to the b5 square. This is characteristic of the Ruy Lopez, also known as the Spanish Opening.

Spite check

A harmless check given by a player who is about to be checkmated that serves no purpose other than to momentarily delay the defeat.

Squeeze

• Gradually increasing the pressure of a bind.
• Sometimes a synonym for zugzwang that is not a mutual zugzwang.

Stalemate

A position in which the player whose turn it is to move has no legal move and his king is not in check. A stalemate results in an immediate draw.

Staunton chessmen

The standard design of chess pieces, required for use in competition.

Stem game

A stem game is the chess game featuring the first use of a particular opening variation. Sometimes, the player or the venue of the stem game is then used to refer to that opening.

Strategy

Evaluation of game positions and setting up goals and longer-term plans for future play, as opposed to a tactic which is a shorter-term plan typically consisting of a well-defined sequence of moves and their contingent moves from a given position in a game.

Strongpoint

A "strongpoint defense" means an opening which defends and retains a central pawn (White: e4 or d4; Black: e5 or d5), as opposed to exchanging the pawn and relinquishing occupation of that central square. (More generically, a strongpoint can be any square heavily defended.)

Sudden death

The most straightforward time control for a chess game: each player has a fixed amount of time available to make all moves.

Swindle

A ruse by which a player in a losing position tricks his opponent, and thereby achieves a win or draw instead of the expected loss. It may also refer more generally to achieving a win or draw from a clearly losing position. See also cheapo.

Swiss tournament

This is a tournament that uses the Swiss system to determine player pairings. The basic idea is that every round each player is paired with an opponent with the same (or close to the same) score. The 33rd Chess Olympiad is an example of a Swiss tournament. See also Round-robin tournament.

Symmetry

A symmetrical position on the chessboard means the positions of one's pieces are exactly mirrored by the opponent's pieces. This most often occurs when Black mimics White's opening moves. Black is said to break symmetry when he makes a move no longer imitating White's move.

T

Tabia or Tabiya

(from Arabic)

1. The initial position of the pieces in Shatranj
2. The final position of a well-known chess opening
3. (from 2) The opening position from which two players familiar with each others' tastes begin play.

Tablebase

See Endgame tablebase.

Tactician

A player who specializes in tactical play, as distinguished from a positional player.

Tactics

Play characterized by short-term attacks and threats, often requiring extensive calculation by the players, as distinguished from positional play.

Takeback

Used in casual games when both players agree to undo one or more moves.

Tarrasch rule

Named after Siegbert Tarrasch, this refers to the general principle that rooks usually should be placed behind passed pawns, either yours or your opponent's.

TD

See Tournament director.

Tempo

An extra move, an initiative at development. A player gains a tempo (usually in the opening) by making the opponent move the same piece twice or defend an enemy piece. In the endgame, one may wish to lose a tempo by triangulation to gain the opposition. (Plural: tempos or tempi).

Text move

This term is used in written analysis of chess games to refer to a move that has been played in the game as opposed to other possible moves. Text moves are usually in bold whereas analysis moves are not.

Theme tournament

A tournament in which every game must begin with a particular opening specified by the organizers, for example the Budapest Gambit (1.d4 Nf6 2.c4 e5).

Theoretical Novelty (TN)

A new move in the opening. Also called simply a "novelty".

Threat

A plan or move that, if left unattended, would result in an immediate depreciation of the opponent's position.

Threefold repetition

A draw may be claimed if the same position occurs three times with the same player to move, and with each player having the same set of legal moves each time (the latter includes the right to take en passant and the right to castle).

Tiebreaks

This refers to a number of different systems that are used to break ties, and thus designate a single winner, where multiple players or teams tie for the same place in a Swiss system chess tournament.

Time

Opportunities to make moves: similar meaning to tempo. A move that does not alter the position significantly is described as "wasting time", and forcing the other player to waste time is described as "gaining time".

Time control

The allowed time to finish a game, usually measured by a chess clock. A time control can require either a certain number of moves be made per time period (e.g., 40 moves in 2½ hours) or it can limit the length of the entire game (e.g., 5 minutes per game for blitz). Hybrid schemes are used, and time delay controls have become popular since the widespread use of digital clocks.

Time delay

A time control which makes it possible for a player to avoid having an ever-decreasing amount of time remaining (as is the case with sudden death). The most important time delays in chess are Bronstein delay and Fischer delay.

Time pressure or time trouble

Having very little time on one's clock (especially less than five minutes) to complete one's remaining moves. See Time control.

Toilet move

Coined by Nigel Short, a quickly played move described as "any move which doesn't immediately jeopardise your position" allowing the player time to visit the toilet while his opponent thinks.

Top board

In team chess, the player who is assigned to face the strongest opponents. Also called first board. Second board faces the next strongest players, followed by third board, and so on. Generally board assignments must be made before the competition begins and players may not switch boards, although reserve players are often allowed as substitutes.

Touched piece rule

The rule requiring a player who touches a piece that has at least one legal move to move that piece (and, if the player moves the piece to a particular square and takes his hand off it, to move it to that square). Castling must be initiated by moving the king first, so a player who touches his rook may be required to move it, without castling. The rule also requires a player who touches an opponent's piece to capture it if possible. A player wishing to touch a piece to adjust its position on a square without being required to move it signals this intent by saying "J'adoube" or "I adjust". This way of playing is common in official games, in favour of clock move.

Tournament

A competition involving more than two players or teams, generally played at a single venue (or series of venues) in a relatively short period of time. A tournament is divided into rounds, with each round consisting either of individual games or matches in the case of knockout tournaments and team tournaments. The assignment of opponents is called pairing, with the most popular systems being round-robin and Swiss. Tournaments are usually referred to by combining the city in which they were played with the year, as in "London 1851", although there are well known exceptions such as "AVRO 1938".

Tournament book

A book recording the scores of all the games in a tournament, usually with analysis of the best or most important games and some background on the event and its participants. One well-known example is Bronstein's Zurich International Chess Tournament 1953. The less comprehensive tournament bulletin is usually issued between the rounds of a prestigious event, giving the players and world media an instant record of the games of the previous round. Individual copies may be bundled together at the conclusion of the event to provide an inexpensive alternative to the tournament book.

Tournament director (TD)

Organizer and arbiter of a tournament, responsible for enforcing the tournament rules and the Laws of Chess. Also tournament controller (chiefly British).

Transposition

Arriving at a position using a different sequence of moves.

Trap

A move which may tempt the opponent to play a losing move. See also Swindle.

Trébuchet

A position of mutual zugzwang in which either player would lose if it is their turn to move.

Triangulation

A technique used in king and pawn endgames (less commonly seen with other pieces) to lose a tempo and gain the opposition.

Two bishops, The

"(The) two bishops". Synonym for: Bishop pair.

U

Undermining

This is a chess tactic (also known as removal of the guard) in which a defensive piece is captured, leaving one of the opponent's pieces undefended or underdefended.

Underpromotion

Promoting a pawn to a rook, bishop, or knight instead of a queen. Rarely seen unless the knight can deliver a crucial check, or when promotion to a rook or a bishop instead of a queen is necessary to avoid stalemate.

Unpinning

the act of breaking a pin. This allows the piece that was formerly pinned to move.

United States Chess Federation (USCF)

This is a non-profit organization, the governing chess organization within the United States, and one of the federations of the FIDE.

Unorthodox opening

See Irregular opening.

V

Vacating sacrifice

A sacrifice made for the purpose of clearing a square for a different piece of the same color.

Valve

A move which opens one line and closes another.

Variant

A chess-like game played using a different board, pieces, or rules than standard chess.

Variation

A sequence of moves or alternative line of play, often applied to the opening. A variation does not have to have been played in a game, it may also be a possibility that occurs only in analysis. The word Variation is also used to name specific sequences of moves within an opening. For an example, the Dragon Variation is part of the Sicilian Defence.

W

Waiting move

A passive but harmless move, which is played while waiting for initiative from the opponent.

Weak square

A square that cannot be easily defended from attack by an opponent. Often a weak square is unable to be defended by pawns (a hole) and can be theoretically occupied by a piece. Exchange or loss of a bishop may make all squares of that bishop's color weak resulting in a "weak square complex" on the light squares or the dark squares.

WFM

Abbreviation for the Woman FIDE Master title.

WGM

Abbreviation for the Woman Grandmaster title.

White

The designation for the player who moves first, even though the corresponding pieces, referred to as "the white pieces", are sometimes actually some other (usually light) color. Similarly, the light-colored squares on the chessboard are often referred to as "the white squares" even though they often are not literally white. See also Black, First-move advantage in chess.

Wild

An extremely unclear or mind–bogglingly complicated position or move.

WIM

Abbreviation for the Woman International Master title.

Win

A victory for one of the two players in a game, which may occur due to checkmate, resignation by the other player, the other player exceeding the time control, or the other player being forfeited by the tournament director. Chess being a zero-sum game, this results in a loss for the other player.

Win/winning position

A position is said to be a win (or a winning position) if one specified side, with correct play, can eventually force a checkmate against any defence (i.e. perfect defence).

Windmill

A combination in which two pieces work together to deliver an alternating series of checks and discovered checks in such a way that the opposing king is required to move on each turn. It is a potent technique since on every other move, the discovered check may allow the non-checking piece to capture an enemy piece without losing a tempo. The most famous example is Torre–Lasker, Moscow 1925. Also called a see-saw.

Wing

The queenside a, b, and c-files, or the kingside f, g, and h-files, also called flank.

Wing Gambit

Is the name given to variations of several openings in which one player gambits a wing pawn, usually the b pawn.

Winning percentage

A number calculated by taking the percentage of games won by a player plus half the percentage of drawn games. Thus, if out of 100 games a player wins 40, draws 32, and loses 28, her winning percentage is 40 plus half of 32, i.e. 56 percent.

Woman FIDE Master (WFM)

A women-only chess title ranking below Woman International Master.

Woman Grandmaster (WGM)

The highest ranking gender-restricted chess title except for Women's World Champion.

Woman International Master (WIM)

A women-only chess title ranking below Woman Grandmaster and above Woman FIDE Master.

Woodpusher

A weak chess player, also referred to as a "fish", "patzer" or "duffer".

World Champion

A winner of the World Chess Championship.

Wrong-colored bishop

See Wrong rook pawn.

Wrong rook pawn

With a bishop, a rook pawn may be the wrong rook pawn, depending on whether or not the bishop controls its promotion square.

X

X-ray attack

Also sometimes used in place of skewer.

Z

Zeitnot

(from the German) See Time pressure.

Zonal Tournaments

Tournaments organised by the FIDE, the first qualifying cycle of the World Chess Championship. Each zonal tournament features top players of a certain geographical zone. The winners are then qualified for the interzonal tournament.

Zugzwang

(from the German) When a player is put at a disadvantage by having to make a move; where any legal move weakens the position. Zugzwang usually occurs in the endgame, and rarely in the middlegame.

Zwischenschach

(from the German) A zwischenzug that is a check.

Zwischenzug

(from the German) An "in-between" move played before the expected reply.

See also

• Glossary of chess problems
• Outline of chess
• Index of chess articles

References

• Brace, Edward R. (1977), An Illustrated Dictionary of Chess, Hamlyn Publishing Group, ISBN 0-600-32920-8 (1989 reprint by Chartwell Books, ISBN 1-55521-394-4) 
• Burgess, Graham (2000), The Mammoth Book of Chess, Carroll & Graf Publishers, ISBN 0-7867-0725-9 
• Evans, Larry (1967), New Ideas in Chess, Cornerstone Library (1984 Dover edition), ISBN 0-486-28305-4 
• Golombek, Harry, ed. (1977), Golombek's Encyclopedia of Chess, Batsford, ISBN 0-517-53146-1 
• Hooper, David; Whyld, Kenneth (1992), The Oxford Companion to Chess (second ed.), Oxford: Oxford University Press, ISBN 0-19-280049-3 
• Horton, Byrne Joseph (1959), Dictionary of modern chess, Owen, ISBN 0-8022-0746-4 
• Pandolfini, Bruce (1996), Chess Thinking: The Visual Dictionary of Chess Moves, Rules, Strategies and Concepts (Fireside Chess Library), Everyman Chess, ISBN 1-85744-480-9 
• Zelepukhin, N. P. (1982), Dictionary of Chess, French & European Pubns, ISBN 0-8288-2350-2 

Chess Outline Rules Terms Pieces History Openings Strategy Tactics Endgame World Championship Tournaments Computers Variants