A book that lists words in groups of synonyms and related concepts is a thesaurus. A thesaurus is designed to help users with exact and nuanced word choice. Thesauruses usually have one of two organizational principles, either they’re organized alphabetically, in what is called dictionary form, or thematically, so that words with similar meanings are grouped together. Most thesauruses simply list the synonyms and/or antonyms, and you may find that you need to do several thesaurus searches and possibly resort to a dictionary. The largest thesaurus in the world is the Historical Thesaurus of the Oxford English Dictionary, which contains more than 920,000 words. The word "thesaurus" is derived from 16th-century New Latin, in turn from Latin thesaurus, from ancient Greek meaning a collection of things which are of big importance or value. This meaning has been largely supplanted by Roget's usage of the term. The entries are also designed for drawing distinctions between similar words and assisting in choosing exactly the right word. Unlike a dictionary, a thesaurus entry does not define words. |