The Collaborative International Dictionary of English v.0.48:

panther \pan"ther\ (p[a^]n"th[~e]r), n. [OE. pantere, F.
   panth[`e]re, L. panthera, Gr. pa`nqhr, prob. fr. Skr.
   pundr[imac]ka a tiger.]
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   1. (Zool.) A large dark-colored variety of the leopard, by
      some Zoologists considered a distinct species. It is
      marked with large ringlike spots, the centers of which are
      darker than the color of the body.
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   2. (Zool.) In America, the name is applied to the puma, or
      cougar, and sometimes to the jaguar.
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   Panther cat (Zool.), the ocelot.

   Panther cowry (Zool.), a spotted East Indian cowry
      (Cypr[ae]a pantherina); -- so called from its color.
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