/ Dictionary / Index D dioptrics: Meaning and Definition of Find definitions for: di•op•trics Pronunciation: (dī-op'triks), [key] — n. (used with a sing. v.) the branch of geometrical optics dealing with the formation of images by lenses. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. dioptric Dior Related Content Daily Word Quiz: loathe Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language