[W/K] :: Cantharis vesicatoria

  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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  Cantharis \Can"tha*ris\ (k[a^]n"th[.a]*r[i^]s), n.; pl.
     Cantharides (k[a^]n*th[a^]r"[i^]*d[=e]z). [L., a kind of
     beetle, esp. the Spanish fly, Gr. kanqari`s.] (Zool.)
     A beetle ({Lytta vesicatoria, syn. Cantharis vesicatoria),
     having an elongated cylindrical body of a brilliant green
     color, and a nauseous odor; the blister fly or blister
     beetle, of the apothecary; -- also called Spanish fly. Many
     other species of Lytta, used for the same purpose, take the
     same name. See Blister beetle, under Blister. The plural
     form in usually applied to the dried insects used in
     medicine.
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