/ Dictionary / Index H hydrase: Meaning and Definition of Find definitions for: hy•drase Pronunciation: (hī'drās, -drāz), [key] — n. Biochem. any of the class of enzymes that catalyze the addition of a water molecule into a compound without causing hydrolysis. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hydrargyrum hydrastine Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language