a machine that uses the energy from liquid fuel or steam to produce movement

a jet engine 喷气式发动机

a car engine 汽车发动机

My car's been having engine trouble recently. 我的汽车发动机最近老出问题。

Compare: motor noun (DEVICE)

the part of a railway train that pulls it along

something that provides power, often economic power, for other things

For much of the 19th century Britain was the workshop of the world and the engine of economic growth. 英国在十九世纪的大部分时期都堪称世界工厂和经济发展引擎。