柯林斯詞典ball bearing (also ball-bearing) (ball bearings) 1. N-COUNT Ball bearings are small metal balls placed between the moving parts of a machine to make the parts move smoothly. 滾珠軸承 返回 ball bearing劍橋詞典a small metal ball or several of these arranged in a ring to make particular parts of a machine move more easily 滾珠；滾珠軸承 返回 ball bearing