/ Dictionary / Index I impregnable: Meaning and Definition of Find definitions for: im•preg•na•ble Pronunciation: (im-preg'nu-bul), [key] — adj. strong enough to resist or withstand attack; not to be taken by force, unconquerable: an impregnable fort. not to be overcome or overthrown: an impregnable argument. im•preg•na•ble Pronunciation: (im-preg'nu-bul), [key] — adj. susceptible to impregnation, as an egg. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: impregnable (Thesaurus) imprecise impregnate Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language