/ Dictionary / Index V vitiate: Meaning and Definition of Find definitions for: vi•ti•ate Pronunciation: (vish'ē-āt"), [key] — -at•ed, -at•ing. to impair the quality of; make faulty; spoil. to impair or weaken the effectiveness of. to debase; corrupt; pervert. to make legally defective or invalid; invalidate: to vitiate a claim. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: vitiate (Thesaurus) vitiable viticetum Related Content Daily Word Quiz: innocuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language