a steam engine; an external combustion engine that performs mechanical work using steam as its working fluid; short for 蒸汽机zhēngqìjī
steam turbine
a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft; short for 汽轮机qìlúnjī or 蒸汽轮机zhēngqìlúnjī