/ Dictionary / Index I inconceivable: Meaning and Definition of Find definitions for: in•con•ceiv•a•ble Pronunciation: (in"kun-sē'vu-bul), [key] — adj. not conceivable; unimaginable; unthinkable unbelievable; incredible. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: inconceivable (Thesaurus) incomputable inconclusive Related Content Daily Word Quiz: sequester Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language