The Collaborative International Dictionary of English v.0.48:

Stank \Stank\, n. [OF. estang, F. ['e]tang, from L. stagnum a
   pool. Cf. Stagnate, Tank a cistern.]
   1. Water retained by an embankment; a pool of water. [Prov.
      Eng. & Scot.] --Robert of Brunne.
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   2. A dam or mound to stop water. [Prov. Eng.]
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   Stank hen (Zool.), the moor hen; -- called also stankie.
      [Prov. Eng.]
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