/ Dictionary / Index S Southern Triangle: Meaning and Definition of Find definitions for: South'ern Tri'angle Pronunciation: [key] — Astron. Astron. the constellation Triangulum Australe. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. southern toad southernwood Related Content Daily Word Quiz: ounterfeit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language