What does "washer" mean?

Washer: 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.

Additional senses

  1. 2.(Plumbing) A fitting, usually having a plug, applied to a cistern, tub, sink, or the like, and forming the outlet opening.
  2. 3.(Zoöl.) The common raccoon.
  3. 4.(Zoöl.) Same as Washerwoman, 2. [Prov. Eng.]

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