/ Thesaurus / I Synonyms of in vain Find synonyms for: Adverb1. vainly, in vainusage: to no avail; "he looked for her in vain"; "the city fathers tried vainly to find a solution"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: penury Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language