drawbar n 1: a strong metal bar bearing a hook to attach something to be pulled
Drawbar \Draw"bar`\, n. (Railroad) (a) An openmouthed bar at the end of a car, which receives a coupling link and pin by which the car is drawn. It is usually provided with a spring to give elasticity to the connection between the cars of a train. (b) A bar of iron with an eye at each end, or a heavy link, for coupling a locomotive to a tender or car. [1913 Webster]