Hamadryas Io

Peacock \Pea"cock`\ (p[=e]"k[o^]k`), n. [OE. pecok. Pea- in this
   word is from AS. pe['a], p[=a]wa, peacock, fr. L. pavo, prob.
   of Oriental origin; cf. Gr. taw`s, taw^s, Per. t[=a]us,
   t[=a]wus, Ar. t[=a]w[=u]s. See {Cock} the bird.]
   1. (Zool.) The male of any pheasant of the genus {Pavo}, of
      which at least two species are known, native of Southern
      Asia and the East Indies.
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   Note: The upper tail coverts, which are long and capable of
         erection, are each marked with a black spot bordered by
         concentric bands of brilliant blue, green, and golden
         colors. The common domesticated species is {Pavo
         cristatus}. The Javan peacock ({Pavo muticus}) is more
         brilliantly colored than the common species.
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   2. In common usage, the species in general or collectively; a
      peafowl.
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   {Peacock butterfly} (Zool.), a handsome European butterfly
      ({Hamadryas Io}) having ocelli like those of peacock.

   {Peacock fish} (Zool.), the European blue-striped wrasse
      ({Labrus variegatus}); -- so called on account of its
      brilliant colors. Called also {cook wrasse} and {cook}.

   {Peacock pheasant} (Zool.), any one of several species of
      handsome Asiatic pheasants of the genus {Polyplectron}.
      They resemble the peacock in color.
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