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thesaurus

reference work
Also known as: synonymy

Quick Summary

A thesaurus is a reference book that groups words with similar meanings together. The term originates from the Latin word thesaurus, meaning treasury. It was metaphorically applied to books containing a treasury of words or information.123

The English scholar Peter Mark Roget published his Thesaurus of English Words and Phrases in 1852, which listed semantically related words into categories. This publication led to the common acceptance of "thesaurus" referring to a book of words and their synonyms. The word also developed a meaning in word processing for a list of related terms used for indexing and retrieval.3

Unlike a dictionary, which defines words and may include pronunciation and etymology, a thesaurus focuses on synonyms and related terms.4

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