/ Dictionary / Index A alloantigen: Meaning and Definition of Find definitions for: al•lo•an•ti•gen Pronunciation: (al"ō-an'ti-jun, -jen"), [key] — n. Immunol. an antigen present in some but not all individuals of the same species, as those in different human blood groups. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. alloantibody allobaric Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language