Zoon balanitis [J. J. Zoon, Dutch dermatologist, 1902–1958] , a benign erythroplasia of the inner surface of the prepuce or the glans penis, characterized histologically by plasma cell infiltration of the dermis and clinically by a moist, erythematous lesion. Plasma cell vulvitis is a corresponding condition in females. Also called balanitis circumscripta plasmacellularis.
