/ Dictionary / Index D diffractive: Meaning and Definition of Find definitions for: dif•frac•tive Pronunciation: (di-frak'tiv), [key] — adj. causing or pertaining to diffraction. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. diffraction grating diffractometer Related Content Daily Word Quiz: agitated Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language