ball bearing

ball bearing (plural ball bearings)

1. (engineering) A bearing assembly which uses spherical bearing balls as the rolling elements.
2. (loosely, often) An individual spherical ball, usually made of steel or other hard material, suitable for use in a ball-based rolling element bearing. In precise usage, each such ball is called a bearing ball or simply ball, and the entire bearing is called the ball bearing.

• roller bearing

• ball bearing retainer
• caged ball bearing