| an engine worked by steam, typically one in which a sliding piston in a cylinder is moved by the expansive action of the steam generated in a boiler. |
steam engine
(click for larger image in new window) An engine in which the energy of hot steam is converted into mechanical power, especially an engine in which the force of expanding steam is used to drive one or more pistons. The source of the steam is typically external to the part of the machine that converts the steam energy into mechanical energy. Compare internal-combustion engine. |