The Collaborative International Dictionary of English v.0.48:

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]

The Collaborative International Dictionary of English v.0.48:

Crab-yaws \Crab"-yaws`\ (kr?b"y?z`), n. (Med.)
   A disease in the West Indies. It is a kind of ulcer on the
   soles of the feet, with very hard edges. See Yaws.
   --Dunglison.
   [1913 Webster]