Power Thesaurus - Power Thesaurus is a fast, comprehensive and easy-to-follow online thesaurus for writers...
Qikipedia - Instant Wikipedia summary cards on any web page
Writefull Thesaurus - A Google Docs add-on that uses AI to give you synonyms
Six Degrees of Wikipedia - Find the shortest path between two subjects
Classic Thesaurus - crowdsourced thesaurus
Newsit - Find the discussion around the page you're looking at!