/ Dictionary / Index T trinal: Meaning and Definition of Find definitions for: tri•nal Pronunciation: (trīn'l), [key] — adj. threefold; triple; trine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Trinacria trinary 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