bushing (n.)youdaoicibaDictYouDict[bushing 词源字典]
"metal sleeve fitted into a machine or hole," 1839, from gerundive of bush "metal lining of the axle hole of a wheel or touch hole of a gun" (1560s), from Middle Dutch busse "box" (cognate with the second element in blunderbuss).[bushing etymology, bushing origin, 英语词源]