thesaurus

play
noun the·sau·rus \thi-ˈsȯr-əs\

Definition of thesaurus

plural

thesauri

play \-ˈsȯr-ˌī, -ˌē\ or

thesauruses

play \-ˈsȯr-ə-səz\
  1. 1a :  a book of words or of information about a particular field or set of concepts; especially :  a book of words and their synonymsb :  a list of subject headings or descriptors usually with a cross-reference system for use in the organization of a collection of documents for reference and retrieval

  2. 2 :  treasury, storehouse

thesaural

play \-ˈsȯr-əl\ adjective

thesaurus was our Word of the Day on 06/14/2015. Hear the podcast!

Did You Know?

In the early 19th century, archaeologists borrowed the Latin word thesaurus to denote an ancient treasury, such as that of a temple. Soon after, the word was metaphorically applied to a book containing a "treasury" of words or information about a particular field. In 1852, the English scholar Peter Mark Roget published his Thesaurus of English Words and Phrases, in which he listed a treasury of related words organized into numerous categories. This work led to the common acceptance of the term "thesaurus" for "a book of words and their synonyms." Finally, during the 1950s, "thesaurus" began being used in the field of word processing to refer to a list of related terms used for indexing and retrieval.

Origin and Etymology of thesaurus

New Latin, from Latin, treasure, collection, from Greek thēsauros


First Known Use: circa 1823


THESAURUS Defined for English Language Learners

thesaurus

play
noun the·sau·rus \thi-ˈsȯr-əs\

Definition of thesaurus for English Language Learners

  • : a book in which words that have the same or similar meanings are grouped together


THESAURUS Defined for Kids

thesaurus

play
noun the·sau·rus \thi-ˈsȯr-əs\

Definition of thesaurus for Students

plural

thesauri

\-ˈsȯr-ˌī, -ˌē\ or

thesauruses

\-ˈsȯr-ə-səz\
  1. :  a book of words and their synonyms



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capable of being altered or controlled

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