1.That which draws, or is used for drawing.
2.pl. (Med.) Two small, pointed rods of metal, formerly used in the treatment called Perkinism.
3.A motor vehicle with a powerful engine and large wheels, used to pull farm equipment such as plows, harvesting machinery, etc., over farm land. Smaller forms of farm tractor are completely open, with only a seat for the driver.
4.A motor vehicle with a driver's cab and a powerful engine, fitted with a coupling at the rear, and designed to pull a large trailer or semi-trailer on the open highway; called also truck tractor. The combination of such a tractor with its trailer is called a tractor-trailer, and is a common form of truck used for commercial shipping of freight.
5.(Aviation) A propeller screw placed in front of the supporting planes of an aeroplane instead of behind them, so that it exerts a pull instead of a push; called also Tractor screw and Tractor propeller.
6.(Aviation) An airplane having one or more tractor propellers; called also tractor airplane.
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