/ Dictionary / Index H hexahydrate: Meaning and Definition of Find definitions for: hex•a•hy•drate Pronunciation: (hek"su-hī'drāt), [key] — n. a hydrate that contains six molecules of water, as magnesium chloride, MgCl&multiplydot;6HO. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hexahemeron hexahydric Related Content Daily Word Quiz: serendipity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language