The Collaborative International Dictionary of English v.0.48:

Pie \Pie\, n. [F. pie, L. pica; cf. picus woodpecker, pingere to
   paint; the bird being perhaps named from its colors. Cf.
   Pi, Paint, Speight.]
   1. (Zool.)
      (a) A magpie.
      (b) Any other species of the genus Pica, and of several
          allied genera. [Written also pye.]
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   2. (R. C. Ch.) The service book.
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   3. (Pritn.) Type confusedly mixed. See Pi.
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   By cock and pie, an adjuration equivalent to "by God and
      the service book." --Shak.

   Tree pie (Zool.), any Asiatic bird of the genus
      Dendrocitta, allied to the magpie.

   Wood pie. (Zool.) See French pie, under French.
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