/ Dictionary / Index A aerostat: Meaning and Definition of Find definitions for: aer•o•stat Pronunciation: (âr'u-stat"), [key] — n. any lighter-than-air aircraft, as a balloon or dirigible. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. aerosphere aerostatic Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language