thesaurus-service
Provides synonym for word, uses remote sites (words.bighugelabs.com, thesaurus.altervista.org, thesaurus.com, etc.)
@apiverve/thesaurus
Thesaurus is a simple tool for getting word synonyms. It returns a list of synonyms.
moby
An open-source website (and CLI) for searching the largest thesaurus in the English language.