The Collaborative International Dictionary of English v.0.48:

Whilk \Whilk\, n. [See Whelk a mollusk.]
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   1. (Zool.) A kind of mollusk, a whelk. [Prov. Eng.]
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   2. (Zool.) The scoter. [Prov. Eng.]
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The Collaborative International Dictionary of English v.0.48:

Whilk \Whilk\, pron.
   Which. [Obs. or Scot.]
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   Note: Whilk is sometimes used in Chaucer to represent the
         Northern dialect.
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