The Collaborative International Dictionary of English v.0.48:

Specter \Spec"ter\, Spectre \Spec"tre\, n. [F. spectre, fr. L.
   spectrum an appearance, image, specter, fr. specere to look.
   See Spy, and cf. Spectrum.]
   1. Something preternaturally visible; an apparition; a ghost;
      a phantom.
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            The ghosts of traitors from the bridge descend,
            With bold fanatic specters to rejoice. --Dryden.
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   2. (Zool.)
      (a) The tarsius.
      (b) A stick insect.
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   Specter bat (Zool.), any phyllostome bat.

   Specter candle (Zool.), a belemnite.

   Specter shrimp (Zool.), a skeleton shrimp. See under
      Skeleton.
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