/ Dictionary / Index S supergiant star: Meaning and Definition of Find definitions for: su'pergiant star' Pronunciation: [key] an exceptionally luminous star whose diameter is more than 100 times that of the sun, as Betelgeuse or Antares. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. super giant slalom superglacial Related Content Daily Word Quiz: menagerie Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language