Source : Webster's Revised Unabridged Dictionary (1913)

Washer \Wash"er\, n. [AS. w[ae]scere.]
   1. One who, or that which, washes.

   2. A ring of metal, leather, or other material, or a
      perforated plate, used for various purposes, as around a
      bolt or screw to form a seat for the head or nut, or
      around a wagon axle to prevent endwise motion of the hub
      of the wheel and relieve friction, or in a joint to form a
      packing, etc.

   3. (Plumbing) A fitting, usually having a plug, applied to a
      cistern, tub, sink, or the like, and forming the outlet
      opening.

   4. (Zo["o]l.) The common raccoon.

   5. (Zo["o]l.) Same as {Washerwoman}, 2. [Prov. Eng.]

Source : WordNet®

washer
     n 1: someone who washes things for a living
     2: seal consisting of a flat disk placed to prevent leakage
     3: a home appliance for washing clothes and linens
        automatically [syn: {automatic washer}, {washing machine}]