thesaurus
4 synonyms and 0 antonyms for thesaurus, grouped by meaning and by how common each one is.
Noun — A reference book or website that groups words by meaning, so you can look up a word and find its synonyms and often its antonyms.
Synonyms
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
Synonyms by Meaning
1. noun
A reference book or website that groups words by meaning, so you can look up a word and find its synonyms and often its antonyms.
“I keep a thesaurus open when I'm editing to avoid repeating myself.”
2. noun
A controlled list of indexing terms and their relationships, used to catalogue and search a collection of documents.
“Articles are tagged using the library's medical subject thesaurus.”
How to Use Thesaurus
The word patterns that sound natural to a native speaker.
Neutral. The plural is thesauruses in ordinary use and thesauri in more formal or academic writing; both are accepted.
Etymology
From Latin thesaurus 'treasure, treasury, storehouse', from Greek thesauros.
Full origin of thesaurus →Frequently Asked Questions
What is the difference between a thesaurus and a dictionary?
A dictionary is organised by headword and tells you what each word means, how it is pronounced and where it came from. A thesaurus is organised by meaning and gives you alternative words that express a similar idea. Writers use both together — the thesaurus to find a candidate, the dictionary to check it fits.
What is the plural of thesaurus?
Both thesauruses and thesauri are correct. Thesauruses is more common in everyday English; thesauri keeps the Latin plural and appears more in academic and library contexts.
Why is it called a thesaurus?
The word is Latin for treasury or storehouse, itself from Greek. The idea is a store of words you can draw on, and the sense of a hoard of treasure is the older meaning of the Latin term.