[W/K] :: Blister plaster

  Blister \Blis"ter\, n. [OE.; akin to OD. bluyster, fr. the same
     root as blast, bladder, blow. See Blow to eject wind.]
     1. A vesicle of the skin, containing watery matter or serum,
        whether occasioned by a burn or other injury, or by a
        vesicatory; a collection of serous fluid causing a
        bladderlike elevation of the cuticle.
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              And painful blisters swelled my tender hands.
                                                    --Grainger.
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     2. Any elevation made by the separation of the film or skin,
        as on plants; or by the swelling of the substance at the
        surface, as on steel.
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     3. A vesicatory; a plaster of Spanish flies, or other matter,
        applied to raise a blister. --Dunglison.
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     Blister beetle, a beetle used to raise blisters, esp. the
        Lytta vesicatoria (or Cantharis vesicatoria), called
        Cantharis or Spanish fly by druggists. See
        Cantharis.
  
     Blister fly, a blister beetle.
  
     Blister plaster, a plaster designed to raise a blister; --
        usually made of Spanish flies.
  
     Blister steel, crude steel formed from wrought iron by
        cementation; -- so called because of its blistered
        surface. Called also blistered steel.
  
     Blood blister. See under Blood.
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