Radical
Radical, from Late Latin radicalis "of roots" and from Latin radix "root", may refer to:
In chemistry:
- A radical (chemistry) is an atom, molecule, or ion, that is likely to take part in chemical reactions
In mathematics:
- Radical symbol (√), a symbol used to indicate the square root or nth root
- Radical of an algebraic group, a concept in algebraic group theory
- Radical of an ideal, an important concept in abstract algebra
- Radical of a ring, in ring theory, a branch of mathematics, a radical of a ring is an ideal of "bad" elements of the ring
- Radical of a module, in the theory of modules, the radical of a module is a component in the theory of structure and classification
- Jacobson radical, the Jacobson radical of a ring, R, consists of those elements in R that annihilate all simple right R-modules
- Nilradical of a ring, the nilradical of a commutative ring is a nilpotent ideal, which is as large as possible
- Nilradical of a Lie algebra, the nilradical of a Lie algebra is a nilpotent ideal, which is as large as possible
- Radical of an integer, a concept in number theory
- Symmetric bilinear form, a concept in linear algebra
- Radical of a Lie algebra, a concept in Lie theory
In medicine:
- Radical surgery, surgery carried out in extreme circumstances and/or with extensive treatment
In linguistics:
- In an inflected language such as English or Spanish, the radical verbs (also called 'radical-changing') are exceptions to the standard patterns of word change (e.g., to be is in most Indo European languages).
- Root (linguistics), also called a "radical", the form of a word after any prefixes and suffixes are removed
- Radical (Chinese character), part of a Chinese character under which it is indexed in a dictionary (also called bùshǒu 部首)
- Radical, one of the three consonants in a Semitic root
- Radical consonant, a consonant articulated with the root of the tongue
In politics:
In religion:
In culture:
- Radical feminism, a current within feminism that focuses on patriarchy as a system of power
- Radical veganism, a radical interpretation of veganism, usually combined with anarchism
- Radical chic, a term coined by Tom Wolfe to describe the pretentious adoption of radical causes by celebrities, socialites, and high society
In architecture:
- Radical Baroque, an architectural style characterized by the curvature of walls and intersection of oval spaces
In music:
Brands, titles and proper names: