Douglas Harper's Etymology Dictionary
Wiktionary
polydactyl
a. polydactylous. n. A polydactylous animal.
WordNet
polydactyl
adj. of or relating to a person (or other vertebrate) having more than the normal number of digits [syn: polydactylous]
Usage examples of "polydactyl".
At the time, it had puzzled her, and it did again now, for in Ailurin a “sixth claw” was an extra dewclaw, which polydactyl cats might have.