The Collaborative International Dictionary of English v.0.48:

Pileate \Pi"le*ate\, Pileated \Pi"le*a`ted\, a. [L. pileatus,
   fr. pileus a felt cap or hat.]
   1. Having the form of a cap for the head.
      [1913 Webster]

   2. (Zool.) Having a crest covering the pileus, or whole top
      of the head.
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   Pileated woodpecker (Zool.), a large American woodpecker
      (Ceophloeus pileatus). It is black, with a bright red
      pointed crest. Called also logcock, and woodcock.
      [1913 Webster]