Real Dictionary

motor in American English
anything that produces or imparts motion
producing or imparting motion
noun: a comparatively small and powerful engine, esp. an internal-combustion engine in an automobile, motorboat, or the like

motor in Automotive Engineering
noun: The motor in a vehicle is the part that uses electricity or fuel to produce movement, so that the vehicle can work.

motor in British English
adjective: producing or causing motion
noun: the engine, esp an internal-combustion engine, of a vehicle
verb: to travel by car

motor in Electrical Engineering
noun: A motor is a rotating device that converts electrical power into mechanical power.

motor in Mechanical Engineering
noun: A motor is a device that changes a form of energy into mechanical energy to produce motion.