Pian \Pian\, n. [Pg. pian, epian, or. Sp. pian; from the native name in South America: cf. F. pian.] (Med.) The yaws. See {Yaws}. [1913 Webster]
Yaws \Yaws\, n. [African yaw a raspberry.] (Med.) A disease, occurring in the Antilles and in Africa, characterized by yellowish or reddish tumors, of a contagious character, which, in shape and appearance, often resemble currants, strawberries, or raspberries. There are several varieties of this disease, variously known as {framboesia}, {pian}, {verrugas}, and {crab-yaws}. [1913 Webster]