The Collaborative International Dictionary of English v.0.48:

Blanket \Blan"ket\, v. t. [imp. & p. p. Blanketed; p. pr. &
   vb. n. Blanketing.]
   1. To cover with a blanket.
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            I'll . . . blanket my loins.          --Shak.
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   2. To toss in a blanket by way of punishment.
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            We'll have our men blanket 'em i' the hall. --B.
                                                  Jonson.
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   3. To take the wind out of the sails of (another vessel) by
      sailing to windward of her.
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   Blanket cattle. See Belted cattle, under Belted.
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