/ Dictionary / Index T triapsidal: Meaning and Definition of Find definitions for: tri•ap•si•dal Pronunciation: (trī-ap'si-dl), [key] — adj. Archit. having three apses. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Trianta triarchy Related Content Daily Word Quiz: abdicate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language