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. 236. Cf. Fill a thill, Deal a plank.]
One of the two long pieces of wood, extending before a vehicle, between which a horse is hitched; a shaft.
The floor of a coal mine.
Thill coupling, a device for connecting the thill of a vehicle to the axle.
© Webster 1913.