Pronunciation: (kas'tur, kä'stur), [key]
1. a person or thing that casts.
2. a small wheel on a swivel, set under a piece of furniture, a machine, etc., to facilitate moving it.
3. a bottle or cruet for holding a condiment.
4. a stand containing a set of such bottles.
5. a metal container for sugar, pepper, etc., having a perforated top to permit sprinkling; dredger; muffineer.
6. Auto.the angle that the kingpin makes with the vertical. Automobiles are usually designed with the upper end of the kingpin inclined rearward (positive caster) for improved directional stability.
(of a wheel) to swivel freely in a horizontal plane. Also,castor (for defs. 2–5).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.