The Collaborative International Dictionary of English v.0.48:

Wiper \Wip"er\, n.
   1. One who, or that which, wipes.
      [1913 Webster]

   2. Something used for wiping, as a towel or rag.
      [1913 Webster]

   3. (Mach.) A piece generally projecting from a rotating or
      swinging piece, as an axle or rock shaft, for the purpose
      of raising stampers, lifting rods, or the like, and
      leaving them to fall by their own weight; a kind of cam.
      [1913 Webster]

   4. (Firearms) A rod, or an attachment for a rod, for holding
      a rag with which to wipe out the bore of the barrel.
      [1913 Webster]

WordNet (r) 3.0 (2006):

wiper
    n 1: a worker who wipes
    2: contact consisting of a conducting arm that rotates over a
       series of fixed contacts and comes to rest on an outlet [syn:
       wiper, wiper arm, contact arm]
    3: a mechanical device that cleans the windshield [syn:
       windshield wiper, windscreen wiper, wiper, wiper
       blade]