‖n. [ Sing. of Aphthæ. ] (Med.)
‖n. pl. [ L., fr. Gr. &unr_; (mostly in pl. &unr_;, Hipp.) an eruption, thrush, fr. &unr_; to set on fire, inflame. ] (Med.) Roundish pearl-colored specks or flakes in the mouth, on the lips, etc., terminating in white sloughs. They are commonly characteristic of thrush. [ 1913 Webster ]