/ Dictionary / Index D demantoid: Meaning and Definition of Find definitions for: de•man•toid Pronunciation: (di-man'toid), [key] — n. Mineral. a brilliant green variety of andradite garnet, used as a gem. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: demantoid (Thesaurus) demand-side demarcate Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language