n. any one of two or more speech sounds that considered variants of the same phoneme. For example, the p sounds of pin and spin are allophones of p; and the t sounds of toe stop and catnip are allophones of t. [ PJC ]

n. [ L. metallum metal + Gr. &unr_; sound. ] (Music) (a) An instrument like a pianoforte, but having metal bars instead of strings. (b) An instrument like the xylophone, but having metallic instead of wooden bars. [ Webster 1913 Suppl. ]