thesaurus

Where does the word "thesaurus" come from? It comes from Greek thēsauros, passing through Latin before entering English (1820s).

Thesaurus’s story begins in Greek: thēsauros meant “treasure, storehouse.” Greek, the root of 'treasure'. By ancient, the word had taken hold in Latin as thesaurus. Roman writers used it for a treasury or storehouse. It reached English by 1820s as thesaurus. Roget's Thesaurus of 1852 fixed the sense 'book of synonyms'. Today, thesaurus means a book of synonyms.

1. Stage 1 · Greek · ancient thēsauros "treasure, storehouse", Greek, the root of 'treasure'.
2. Stage 2 · Latin · ancient thesaurus "treasury", Roman writers used it for a treasury or storehouse.
3. Stage 3 · English · 1820s thesaurus "dictionary", Roget's Thesaurus of 1852 fixed the sense 'book of synonyms'.