DICT.TW Dictionary Taiwan

 Tract·or n.
 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.
 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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 Tractor screw or  Tractor propeller. Aviation A propeller screw placed in front of the supporting planes of an airplane instead of behind them, so that it exerts a pull instead of a push. Hence, Tractor monoplane, Tractor biplane, etc.  This is the most common arrangement for propellers on modern airplanes.
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