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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.
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circa 1823, in the meaning defined at sense 2
New Latin, from Latin, treasure, collection, from Greek thēsauros
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From the Editors at Merriam-Webster
More than just a collection of related words—Peter Mark Roget intended his Thesaurus to be a classification of all knowledge
the scenic route
the scheme of things
the scientific method
Time Traveler for thesaurus
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More Definitions for thesaurus
See the full definition for thesaurus in the English Language Learners Dictionary
More from Merriam-Webster on thesaurus
Rhyming Dictionary: Words that rhyme with thesaurus
Thesaurus: All synonyms and antonyms for thesaurus
Spanish Central: Translation of thesaurus
Nglish: Translation of thesaurus for Spanish Speakers
Britannica English: Translation of thesaurus for Arabic Speakers
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a tendency to relapse
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