/ Dictionary / Index B blastoff: Meaning and Definition of Find definitions for: blast•off Pronunciation: (blast'ôf", -of", bläst'-), [key] — n. Aerospace. the launching of a rocket, guided missile, or spacecraft. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: blastoff (Thesaurus) blastodisk blastogenesis Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language