The Collaborative International Dictionary of English v.0.48:

Blanket \Blan"ket\, n. [F. blanchet, OF. also blanket, a woolen
   waistcoat or shirt, the blanket of a printing press; prop.
   white woolen stuff, dim. of blanc white; blanquette a kind of
   white pear, fr. blanc white. See Blank, a.]
   1. A heavy, loosely woven fabric, usually of wool, and having
      a nap, used in bed clothing; also, a similar fabric used
      as a robe; or any fabric used as a cover for a horse.
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   2. (Print.) A piece of rubber, felt, or woolen cloth, used in
      the tympan to make it soft and elastic.
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   3. A streak or layer of blubber in whales.
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   Note: The use of blankets formerly as curtains in theaters
         explains the following figure of Shakespeare. --Nares.
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               Nor heaven peep through the blanket of the dark
               To cry, "Hold, hold!"              --Shak.
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   Blanket sheet, a newspaper of folio size.

   A wet blanket, anything which damps, chills, dispirits, or
      discour?ges.
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