What is "zygodactylic"

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.

a. (context zoology English) 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.