Where does the Thesaurus originated from? The Origin? 'Late 16th century: via Latin from Greek thēsauros ‘storehouse, treasure’. The original sense ‘dictionary or encyclopedia’ was narrowed to the current meaning by the publication of Roget's Thesaurus of English Words and Phrases (1852).'

"Language reference book organized to help in finding words related to a core concept but having different shades of meaning (connotations). Unlike a dictionary (which is organized to help in finding the meaning if you know the word), a thesaurus requires you to know the intended meaning to help find the correct word. Unlike a dictionary of synonyms (which is an alphabetical list of related words), a thesaurus is structured around ideas and serves as a treasury of knowledge. First English language thesaurus (the 'Roget's Thesaurus') was created in 1852 by the UK surgeon Dr Peter Mark Roget (1779-1869)".

https://en.wikipedia.org/wiki/Thesaurus

The Thesaurus (thi-so-ras a treasury: a storehouse of knowledge)

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The Thesaurus helps you to find the most suitable word for a particular situation.

You supply the word and the thesaurus presents you with many synonyms or options.
These extend your vocabulary and enrich your writing and speaking skills.
The antonym is often given.

Example of a thesaurus entry:

Success: best-seller, celebrity, eminence, fame, fortune, hit, luck, prosperity, sensation, star, triumph, winner.
Antonyms: disaster, failure

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