The beam of a boat is its maximum width.
Bit-by-Bit, Port Side
Bit-by-Bit - a Catana 47 catamaran.
Boom
Booms on modern sailboats run horizontally from the mast aft. On an old ship, the boom was a spar which extended the foot of the sail.
Bosun’s chairs
Bosun’s chairs were seats suspended on a tether of rope, used to haul or lower a person.
Bow
The bow of the boat is the tapered front portion, designed to split the water into the wake.
