Noun

1. A wheeled assembly attached to a larger object at its base to facilitate rolling. A caster usually consists of
   • a wheel, which may be plastic, a hard elastomer, or metal
   • an axle
   • a mounting provision, usually a stem, flange, or plate
   • (sometimes) a swivel which allows the caster to rotate for steering

   Many office chairs roll on a set of casters.

2. A shaker with a perforated top for sprinkling condiments such as sugar, salt, pepper, etc.