Breadcrumb Home > Dictionary > Index A acquired immunity: Meaning and Definition of Find definitions for: acquired' immu'nity Pronunciation: [key] — Immunol. Immunol. immunity arising from exposure to antigens. Cf. natural immunity. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. acquired immune deficiency syndrome acquiree ✖ Related Content Daily Word Quiz: legerdemain Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language