The Collaborative International Dictionary of English v.0.48:

Metope \Met"o*pe\, n. [NL., fr. Gr. ?; meta` with, between + ?
   opening, hole, the hole in the frieze between the beam ends.]
   1. (Arch.) The space between two triglyphs of the Doric
      frieze, which, among the ancients, was often adorned with
      carved work. See Illust. of Entablature.
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   2. (Zool.) The face of a crab.
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   Note: In the Parthenon, groups of centaurs and heroes in high
         relief occupy the metopes.
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