blistern.[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.()And painful blisters swelled my tender hands. (Grainger.)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.()3. A vesicatory; a plaster of Spanish flies, or other matter, applied to raise a blister.(Dunglison.)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.()v. i. To be affected with a blister or blisters; to have a blister form on.()Let my tongue blister. (Shak.)v. t.1. To raise a blister or blisters upon.()My hands were blistered. (Franklin.)2. To give pain to, or to injure, as if by a blister.()This tyrant, whose sole name blisters our tongue. (Shak.)