mocker

from WordNet (r) 3.0 (2006)

mocker
    n 1: someone who jeers or mocks or treats something with
         contempt or calls out in derision [syn: {scoffer},
         {flouter}, {mocker}, {jeerer}]
    2: long-tailed grey-and-white songbird of the southern United
       States able to mimic songs of other birds [syn:
       {mockingbird}, {mocker}, {Mimus polyglotktos}]

from The Collaborative International Dictionary of English v.0.48

Mocker \Mock"er\, n.
   1. One who, or that which, mocks; a scorner; a scoffer; a
      derider.
      [1913 Webster]

   2. A deceiver; an impostor.
      [1913 Webster]

   3. (Zool.) A mocking bird.
      [1913 Webster] mockernut

from Moby Thesaurus II by Grady Ward, 1.0

33 Moby Thesaurus words for "mocker":
      ape, conformist, copier, copycat, copyist, counterfeiter, cuckoo,
      dissembler, dissimulator, echo, echoer, echoist, faker, forger,
      hypocrite, imitator, impersonator, impostor, mime, mimer, mimic,
      mimicker, mockingbird, monkey, parrot, phony, plagiarist,
      poll-parrot, polly, polly-parrot, poseur, sheep, simulator

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