from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A book of synonyms, often including related and contrasting words and antonyms.
  • noun A book of selected words or concepts, such as a specialized vocabulary of a particular field, as of medicine or music.

from The Century Dictionary.

  • noun A treasury; a store; especially, thesaurus verborum, or simply thesaurus, a treasury of words; a lexicon.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A treasury or storehouse; hence, a repository, especially of knowledge; -- often applied to a comprehensive work, like a dictionary or cyclopedia.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A publication, usually in the form of a book, that provides synonyms (and sometimes antonyms) for the words of a given language.
  • noun archaic A dictionary or encyclopedia.
  • noun information science A hierarchy of subject headings—canonic titles of themes and topics, the titles serving as search keys.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a book containing a classified list of synonyms


from The American Heritage® Dictionary of the English Language, 4th Edition

[Latin thēsaurus, treasury, from Greek thēsauros.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

16th century, from Latin thēsaurus, from Ancient Greek θησαυρός (thēsauros, "storehouse, treasure"); its current English usage/meaning was established soon after the publication of Peter Roget's Thesaurus of English Words and Phrases in 1852


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  • What's a synonym for "thesaurus"?

    May 7, 2008

  • thesaurus: A book, publication, volume, manuscript, opus in which one finds, seeks, searches, locates, traces, ferrets for a synonym, alternative, equivalent, similar, substitute word, lexeme, term.

    July 23, 2008

  • Welcome.

    July 19, 2009

  • Nice sign bilby!!

    Synonyms of Thesaurus: glossary, language reference book, lexicon, onomasticon, reference book, sourcebook, storehouse of words, terminology, treasury of words, vocabulary, word list

    July 19, 2009

  • Rock and Roll, Thesaurusized.

    August 20, 2009

  • December 29, 2010

  • From the Greek word meaning "treasury".

    December 30, 2010