名詞 linchpin:

1. a central cohesive source of support and stability
   同義詞：anchor, mainstay, keystone, backbone, lynchpin
2. pin inserted through an axletree to hold a wheel on
   同義詞：lynchpin

1. Controlling wages is the linchpin of the Government'spolicies.
   控制工資是政府政策的關鍵。

linchpin 或 lynch.pin

n.（名詞）
A locking pin inserted in the end of a shaft, as in an axle, to prevent a wheel from slipping off.
車轄，制輪：裝在轅底部，如車軸上用來預防車輪滑動鎖栓
A central cohesive element:
關鍵：重要凝聚力的因素：
例句：
Reduced spending is the linchpin of their economic program.
減少支出是這個經(jīng)濟計劃的關鍵

來源：
Middle English linspin
中古英語 linspin
lins [linchpin] from Old English lynis
lins [栓] 源自 古英語 lynis
pin [pin] from Old English pinn * see pin
pin [椎] 源自 古英語 pinn *參見 pin