ball bearing

American  

noun

Machinery.

1. 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.

2. any of the balls so used.

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ball bearing British  

noun

1. 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

2. a metal ball, esp one used in such a bearing

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ball bearing Scientific  

1. A ring-shaped track containing hard metal balls that roll freely, used to reduce friction where a rotating element (such as an axle) is attached to a fixed point.

2. A hard ball used in such a track.

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Other Word Forms

• ball-bearing adjective

Etymology

Origin of ball bearing

First recorded in 1880–85

Example Sentences

Three people, including the defendant, were injured in the stunt, during which he first threw a large inflatable ball bearing the words “Kick out oil” onto the pitch before becoming entangled in a steel wire.

From Washington Times • Jul. 11, 2023

To protect against damage from a major earthquake, the slab is held up by six seismic isolators, each about 5 feet in diameter, with a ball bearing inside.

From Los Angeles Times • Jul. 6, 2023

After the baking, a gumball-like dispenser adds a ball bearing to each crucible and shakes it to grind the new substance into a fine powder that’s loaded onto a slide.

From Science Magazine • Apr. 20, 2023

The Epley maneuver is designed to guide the ear rocks out of the canal, a bit like those puzzle toys you tilt to roll a ball bearing through an enclosed maze.

From Slate • Apr. 17, 2023

Like gripping a ball bearing as hard as you can.

From "Everything Sad Is Untrue" by Daniel Nayeri