What is 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 called?

zygodactylic — 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. (Webster's 1913.)

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