THILL, n. The shaft of a cart, gig or other carriage. The thills are the two pieces of timber extending from the body of the carriage on each side of the last horse, by which the carriage is supported in a horizontal position.
Thill Thill, n. [OE. thille, AS. ?ille a board, plank, beam, thill; akin to ?el a plank, D. deel a plank, floor, G. diele, OHG. dili, dilla, Icel. ?ilja a plank, planking, a thwart, ?ili a wainscot, plank; cf. Skr. tala a level surface. [root]236. Cf. Fill a thill, Deal a plank.] 1. One of the two long pieces of wood, extending before a vehicle, between which a horse is hitched; a shaft. 2. (Mining) The floor of a coal mine. --Raymond. Thill coupling, a device for connecting the thill of a vehicle to the axle.