[1] : The Collaborative International Dictionary of English v.0.48

cockatoo \cock`atoo"\ ko^k`.at=oo", n. malayan
   kakat=ua. zool.
   a bird of the parrot family, of the subfamily cacatuinae,
   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
see also:
cacatuinae broad-crested cockatoo plictolophus cristatus cacatua cristatus cacatua galerita plictolophus galeritus 
palm cockatoo great black cockatoo probosciger aterrimus microglossus aterrimus 

[2] : WordNet (r) 2.0

cockatoo
     n : white or light-colored crested parrot of the australian
         region; often kept as cage birds

Cockatoo >> C Words
Cockatoo, definition of term: Cockatoo
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