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

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.

From BBC

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.

From New York Times

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.

From Los Angeles Times

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.

From BBC

Residents of North Enid Avenue in Azusa, Calif., would find a broken window in their house or car and a telltale ball bearing nearby.

From New York Times