1) Congenital disorder 
Polymelia (from Greek πολυ- = `many` plus μέλος (plural μέλεα) = `limb`) is a birth defect involving limbs (a type of dysmelia), in which the affected individual has more than the usual number of limbs. In humans and most land-dwelling animals, this means having five or more limbs. The extra limb is most commonly shrunken and/or ...
A developmental defect in which there are supernumerary limbs or parts of limbs. ... Origin: poly-+ G. Melos, limb ... (05 Mar 2000) ... 
Type: Term Pronunciation: pol′ē-mē′lē-ă Definitions: 1. A developmental defect in which supernumerary limbs or parts of limbs are present.