a small, powerful and strongly-built
a small, purpose-built object which guides and directs larger vessels to their destination, often through a difficult or complicated passage
a sturdy boat that guides large boats in and out of harbors
Strong v-hull shaped boat used for maneuvering ships into and out of port and to carry supplies. A ship is too powerful to pull up to the wharf on its own. It cuts power and lets the tug nudge it in. Generally barges are pushed by towboats, not tugs.
a small boat designed for towing vessels such as barge; has great manoeuvrability and engine power; also known simply as tug
strongly built, small tonnage vessel especially designed for towing
A small, powerful boat used to help move barges and ships in confined areas.