/ Dictionary / Index T triene: Meaning and Definition of Find definitions for: tri•ene Pronunciation: (trī'ēn), [key] — n. Chem. any compound containing three double bonds. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. tried-and-true triennial Related Content Daily Word Quiz: fresco Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language