/ Dictionary / Index O opsonic: Meaning and Definition of Find definitions for: op•son•ic Pronunciation: (op-son'ik), [key] — adj. Immunol. of, pertaining to, or influenced by opsonin; capable of promoting phagocytosis. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. -opsis opsonify Related Content Daily Word Quiz: hedonist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language