One that drives, as the operator of a motor vehicle. A tool, such as a screwdriver or hammer, that is used for imparting forceful pressure on another object. A machine part that transmits motion or power to another part. Computer Science A piece of software that enables a computer to communicate with a peripheral device. Sports A golf club with a wide head and a long shaft, used for making long shots from the tee. Nautical A jib-headed spanker.