/ Dictionary / Index O oxidase: Meaning and Definition of Find definitions for: ox•i•dase Pronunciation: (ok'si-dās", -dāz"), [key] — n. Biochem. any of a class of oxidoreductases that catalyze the oxidation of a substrate by molecular oxygen with the formation, in most cases, of hydrogen peroxide. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: oxidase (Thesaurus) oxidant smog oxidate Related Content Daily Word Quiz: mongrel Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language