The Collaborative International Dictionary
Zygodactylous
Zygodactylic \Zyg`o*dac"ty*lic\, Zygodactylous \Zyg`o*dac"tyl*ous\ (?; 277), a. [Gr. zygo`n a yoke, pair + ? finger, toe: cf. F. zygodactyle.] (Zo["o]l.) Yoke-footed; having the toes disposed in pairs; -- applied to birds which have two toes before and two behind, as the parrot, cuckoo, woodpecker, etc.
Wiktionary
zygodactylous
a. (context ornithology English) Having two toes pointing forward, and two toes pointing backward.