zygodactyl

n. type of bird having two toes in front and two toes in back on each foot

adj. having two toes in front and two toes in back on each foot (especially pertaining to birds)

In biology, dactyly is the arrangement of (fingers and toes) on the hands, feet, or sometimes wings of a tetrapod animal. It comes from the Greek word δακτυλος = "finger".Sometimes the ending "-dactylia" is used. The derived adjectives end with "-dactyl" or "-dactylous".
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Adjective
1. (of bird feet) having the first and fourth toes directed backward the second and third forward
(antonym) heterodactyl

(n.)
Alt. of Zygodactyle
  

Having two toes pointing forward and two backwards