/ Dictionary / Index I imperceptible: Meaning and Definition of Find definitions for: im•per•cep•ti•ble Pronunciation: (im"pur-sep'tu-bul), [key] — adj. very slight, gradual, or subtle: the imperceptible slope of the road. not perceptible; not perceived by or affecting the senses. —n. something not capable of being perceived by the senses: metaphysical speculation about imperceptibles. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: imperceptible (Thesaurus) imperator imperception 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