/ Dictionary / Index T trihedron: Meaning and Definition of Find definitions for: tri•he•dron Pronunciation: (trī-hē'drun), [key] — pl. -drons, -dra the figure determined by three planes meeting in a point. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. trihedral trihydrate Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language