motor UK /ˈməʊtə/US /ˈmoʊtəɹ/noun 6verb 4adjective 2forms 3 noun6 •a machine that uses energy of some kind to make wheels or other parts turnThe door can close by itself because there's a small motor built into it. •Any protein capable of converting chemical energy into mechanical work. •(figurative) A source of power for something; an inspiration; a driving force. •A motor car, or automobile, sometimes extended to other powered vehicles, such as goods vehicles.Nice motor!Motor insurance is expensive for youngsters. •(slang) The fermenting mass of fruit that is the basis of pruno, or "prison wine". •(literary, no longer used) The controller or prime mover of the universe; God. verb4 •(old-fashioned) To make a journey by motor vehicle; to drive.On Saturday we motored down to Plymouth. •(informal, figurative) To progress at a brisk pace.Sales were slow at first, but now things are really motoring. •(slang) To leave.I gotta motor. •To rotate a jet engine or turboprop using the engine's starter, without introducing fuel into the engine.During startup, the engine should be motored for 20 to 30 seconds to allow the shafts to straighten out, as they may have become bowed under their own weight while the airplane was sitting on the ground. adjective2 •Relating to the ability to move.She has excellent motor skills. •Propelled by an internal combustion engine (as opposed to a steam engine or turbine).A motor yacht for its size has about 30 per cent more accommodations than a steamer of the same size. — 1915 formsmotored · motoring · motors