- a bearing consisting of a number of hard balls running in grooves in the surfaces of two concentric rings, one of which is mounted on a rotating or oscillating shaft or the like.
- any of the balls so used.
- a bearing consisting of a number of hard steel balls rolling between a metal sleeve fitted over the rotating shaft and an outer sleeve held in the bearing housing, so reducing friction between moving parts while providing support for the shaft
- a metal ball, esp one used in such a bearing
