TUG (3)

Tug, n. 1. 1. A pull with the utmost effort, as in the athletic contest called tug of war; a supreme effort.
At the tug he falls, Vast ruins come along, rent from the smoking walls. Dryden. 2. 2. A sort of vehicle, used for conveying timber and heavy articles. Halliwell.
3. 3. (Naut.) A small, powerful steamboat used to tow vessels; — called also steam tug, tugboat, and towboat.
4. 4. A trace, or drawing strap, of a harness.
5. 5. (Mining.) An iron hook of a hoisting tub, to which a tackle is affixed.
Tug iron, an iron hook or button to which a tug or trace may be attached, as on the shaft of a wagon.