zygodactyl

from WordNet (r) 3.0 (2006)

zygodactyl
    adj 1: (of bird feet) having the first and fourth toes directed
           backward the second and third forward [ant:
           {heterodactyl}]

from The Collaborative International Dictionary of English v.0.48

Zygodactyl \Zyg`o*dac"tyl\, Zygodactyle \Zyg`o*dac"tyle\, n.
   [See {Zygodactylic}.] (Zool.)
   Any zygodactylous bird.
   [1913 Webster]

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