A self-powered vehicle, especially a locomotive, used for pulling cars along a track.
A person or group of people which influence a larger group; a driving force.
Anything used to effect a purpose; any device or contrivance; an agent.
A large construction used in warfare, such as a battering ram, catapult etc.
The part of a car or other vehicle which provides the force for motion, now especially one powered by internal combustion.
A complex mechanical device which converts energy into useful motion or physical effects.
A software or hardware system responsible for a specific technical task (usually with qualifying word).
A train pulled by a steam locomotive.