Synonyms for Mocker (same or very similar meaning)
WordNet sense 1 (someone who jeers or mocks or treats something with contempt or calls out in derision):
flouter, scoffer, jeerer
WordNet sense 2 (long-tailed grey-and-white songbird of the southern United States able to mimic songs of other birds):
mockingbird, Mimus polyglotktos
From the ODE community, based on WordNet
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