自行车的drop-out,中文应该怎么翻译，具体指哪个部件

drop-out是自行车部件的名称，找不到相应的中文解释或翻译。
Google字典对dropout的解释：
A U-shaped slot at the end of a fork on a bicycle, made to receive the axle and enabling the wheel to be changed rapidly
维基字典的解释：
A bicycle dropout is a type of fork end that allows the rear wheel to be removed without first derailing the chain. The more inclusive term fork end refers to a slot in a frame or fork where the axle of the wheel is attached.
请帮忙翻译drop-out

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