/ Dictionary / Index T Triangulum Australe: Meaning and Definition of Find definitions for: Tri•an•gu•lum Aus•tra•le Pronunciation: (trī-ang'gyu-lum ô-strā'lē), [key] — Astron. gen. Tri•an•gu•li Aus•tra•lis(trī-ang'gyu-lī" ô-strā'lis).Astron. the Southern Triangle, a southern constellation between Pavo and Circinus. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Triangulum triannual Related Content Daily Word Quiz: reclusive Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language