(1):

(n.) 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.

(2):

(n.) One who, or that which, washes.

(3):

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

(4):

(n.) The common raccoon.

(5):

(n.) Same as Washerwoman, 2.