The Collaborative International Dictionary of English v.0.48:
Webfoot \Web"foot`\, n.; pl. Webfeet. [1913 Webster] 1. A foot the toes of which are connected by a membrane. [1913 Webster] 2. (Zool.) Any web-footed bird. [1913 Webster]WordNet (r) 3.0 (2006):
webfoot n 1: a foot having the toes connected by folds of skin