Source : Webster's Revised Unabridged Dictionary (1913)

Apteryx \Ap"te*ryx\, n. [Gr. 'a priv. + pte`ryx wing. Cf.
   {Aptera}.] (Zo["o]l.)
   A genus of New Zealand birds about the size of a hen, with
   only short rudiments of wings, armed with a claw and without
   a tail; the kiwi. It is allied to the gigantic extinct moas
   of the same country. Five species are known.

Source : WordNet®

apteryx
     n : nocturnal flightless bird of New Zealand having a long neck
         and stout legs; only surviving representative of the
         order Apterygiformes [syn: {kiwi}]