The Collaborative International Dictionary of English v.0.48:

Cockatoo \Cock`a*too"\ (k[o^]k`[.a]*t[=oo]"), n. [Malayan
   kakat[=u]a.] (Zool.)
   A bird of the Parrot family, of the subfamily Cacatuin[ae],
   having a short, strong, and much curved beak, and the head
   ornamented with a crest, which can be raised or depressed at
   will. There are several genera and many species; as the
   broad-crested cockatoo (Plictolophus cristatus or
   Cacatua cristatus), the sulphur-crested (Cacatua galerita
   or Plictolophus galeritus), etc. The palm cockatoo or
   great black cockatoo of Australia is Probosciger
   aterrimus (formerly Microglossus aterrimus).
   [1913 Webster +PJC]