 thumb in general usage, a thesaurus is a reference work that lists words grouped together according to similarity of meaning (containing synonyms and sometimes antonyms), in contrast to a dictionary, which provides definitions for words, and generally lists them in alphabetical order. the main purpose of such reference works is to help the user âto find the word, or words, by which [an] idea may be most fitly and aptly expressedâ â to quote peter mark roget, architect of the best known thesaurus in the english language.roget, peter. 1852. thesaurus of english language words and phrases although including synonyms, a thesaurus should not be taken as a complete list of all the synonyms for a particular word. 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 give the definition of words. ==etymology== the word "thesaurus" is derived from 16th-century new latin, in turn from latin thÄsaurus, which is the latinisation of the greek  (thÄsauros), "treasure, treasury, storehouse"."thesaurus". online etymology dictionary. the word thÄsauros is of uncertain etymology. douglas harper derives it from the root of the greek verb ÏÎ¹Î¸Î­Î½Î±Î¹ tithenai, "to put, to place." robert beekes rejected an indo-european derivation and suggested a pre-greek suffix .r. s. p. beekes, etymological dictionary of greek, brill, 2009, p. 548. the meaning "collection of words arranged according to sense" is first attested in 1852 in roget's title and thesaurer is attested in middle english for "treasurer". ==history==  in antiquity, philo of byblos authored the first text that could now be called a thesaurus. in sanskrit, the amarakosha is a thesaurus in verse form, written in the 4th century. the first modern thesaurus was roget's thesaurus, first compiled in 1805 by peter mark roget, and published in 1852. since its publication it has never been out of print and is still a widely used work across the english-speaking world.http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199254729.001.0001/acprof-9780199254729-chapter-1 entries in roget's thesaurus are liste
Dictionaries_by_type Information_science Knowledge_representation Lexical_semantics Library_science Reference_works Thesauri