Definition of washer

• n. - One who, or that which, washes.
• 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.
• n. - A fitting, usually having a plug, applied to a cistern, tub, sink, or the like, and forming the outlet opening.
• n. - The common raccoon.
• n. - Same as Washerwoman, 2.