/ Dictionary / Index H hydroquinone: Meaning and Definition of Find definitions for: hy•dro•qui•none Pronunciation: (hī"drō-kwi-nōn', -dru-kwin'ōn), [key] — n. Chem. a white, crystalline compound, CHO, formed by the reduction of quinone: used chiefly in photography and to inhibit autoxidation reactions. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hydrops hydrorhiza Related Content Daily Word Quiz: lyceum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language