Noun
torque converter (plural torque converters)
(mechanical engineering) A device that converts the rotational output of a prime mover into work by driving a rotational load. A torque converter functions as a clutch and reduction gear to allow loose coupling between the driver and the driven, letting the drive (such as a motor or engine) rotate at different speeds from the load (such as a wheel).
The automatic transmission 's torque converter is another important application for power transmission with lubricants. Source: Internet
Single disk clutch on manual transmission cars, larger torque converter on automatics. Source: Internet