ball bearing

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.

ball bearing

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

ball bearing

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.

Other Word Forms

• ball-bearing adjective

Word History and Origins

Origin of ball bearing¹

First recorded in 1880–85

Example Sentences

The man, in his 30s, was injured after being hit with a ball bearing, a small metal projectile fired by catapults.

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They also found an air pistol, an SS-style skull mask, goggles and a respirator, fighting gloves with hardened knuckles, pellets, ball bearings, and hunting tips for crossbow arrows.

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They said that a slingshot and ball bearings were found on his property, which was on the same block where the crimes were carried out.

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For about 10 years, police said in a statement, King terrorized the neighborhood by shooting metal ball bearings with a slingshot, breaking house windows, car windshields and nearly striking neighbors themselves.

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The 81-year-old man is accused of firing ball bearings from a slingshot at dozens of local homes, breaking windows and narrowly missing people.

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