基本解釋[動力][車輛] 下止點英英字典柯林斯英英字典 the position of the crank of a reciprocating engine when the piston is at its nearest point to the crankshaft (Also called outer dead centre) bottom dead centre劍橋字典bottom dead centre柯林斯字典專業(yè)釋義交通運輸工程下止點下死點物理學下止點下死點