A reference book or online resource that lists words grouped together according to similarity of meaning (containing synonyms and sometimes antonyms).

She used a thesaurus to find a more precise word for her essay.

A repository or storehouse of knowledge, information, or treasure.

The scholar regarded the monastery library as a thesaurus of medieval lore.

In information science, a structured and controlled vocabulary that shows semantic relationships between terms for use in indexing and retrieval.

The digital archive employs a domain-specific thesaurus to ensure consistent subject tagging.

thesaurusadjective

Relating to or functioning as a thesaurus.

She enabled the thesaurus option to suggest alternative words.