/ Dictionary / Index T trihedral: Meaning and Definition of Find definitions for: tri•he•dral Pronunciation: (trī-hē'drul), [key] — adj. Geom. having, or formed by, three planes meeting in a point: a trihedral angle. —n. a trihedron. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. trigraph trihedron Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language