linchpin

名词

1. 1

   关键、核心、支柱

   She was the linchpin of the whole rescue operation.

   她是整场救援行动的关键人物。

2. 2

   车轴销、制轮楔机械

   The wheel came off after the linchpin worked loose.

   车轴销松脱后，轮子就掉了下来。