motor

n. 1 thing that imparts motion. 2 machine (esp. One using electricity or internal combustion) supplying motive power for a vehicle or other machine. 3 = *car 1. 4 (attrib.) A giving, imparting, or producing motion. B driven by a motor (motor-mower). C of or for motor vehicles. D anat. Relating to muscular movement or the nerves activating it. v. Go or convey in a motor vehicle. [latin: related to *move]

n. One who, or that which, imparts motion; a source of mechanical power.