Know-it-all

From Wikipedia, the free encyclopedia

Cliff Clavin of Cheers, a famous fictional know-it-all

A know-it-all is a person who believes that he or she is extremely knowledgeable, and is determined to demonstrate his or her perceived intelligence at every opportunity. A know-it-all boasts about being an expert on a given subject, although his or her actual knowledge is often (but not always) limited or non-existent.

A know-it-all will invariably dispute others. For instance, someone may present a conflicting opinion or make a recommendation, but the know-it-all will act as though it had already been suggested, analyzed, and discounted. A know-it-all may also disregard or devalue advice from someone who actually has the knowledge the know-it-all purports to have.

Know-it-all may also refer to a legitimate expert who flaunts his or her knowledge.

Someone who really does possess a wealth of knowledge on various topics, but does not necessarily flaunt such knowledge, may be called a polymath.

The term know-it-all has also been used to refer to various projects, such as Wikipedia [1] and Cyc [2], which attempt to encapsulate the broadest possible range of human knowledge.