The Collaborative International Dictionary of English v.0.48:

Plank \Plank\, v. t. [imp. & p. p. Planked; p. pr. & vb. n.
   Planking.]
   1. To cover or lay with planks; as, to plank a floor or a
      ship. "Planked with pine." --Dryden.
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   2. To lay down, as on a plank or table; to stake or pay cash;
      as, to plank money in a wager. [Colloq. U.S.]
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   3. To harden, as hat bodies, by felting.
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   4. (Wooden Manuf.) To splice together the ends of slivers of
      wool, for subsequent drawing.
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   Planked shad, shad split open, fastened to a plank, and
      roasted before a wood fire.
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