At Sea Glossary - B
backstay
A stay (line or cable) used to support the mast. The backstay runs from the masthead to the stern and helps keep the mast from falling forward.
backwinded
The state of a sail with the wind pushing on the wrong side of it, causing it to be pushed away from the wind.
ballast
A weight at the bottom of a boat to keep it stable. Ballasts can be placed inside the hull of the boat or externally in a keel.
beam
1) The widest part of a boat.
2) Abeam, at a right angle to the length of the boat.
3) Sturdy wooden timbers running across the width of a boat. Used to support the deck of a wooden boat.
beam reach
The point of sail with the wind coming from abeam.
bearing
The direction of an object from the observer.
beat
To sail on a tack toward the wind.
beating
Tacking. To sail against the wind by sailing on alternating tacks.
berth
1) A place where a boat or ship can be secured.
2) A safe, cautious distance, as in to give something a "wide berth."
bilge
The lowest part of the interior of the boat where water collects.
bilge pump
A mechanical, electrical, or manually operated pump used to remove water from the bilge.
bimini
A cover used to shelter the cockpit from the sun.
bitt
Any of the deck posts, often in pairs, around which lines or chains are wound and held fast.
bitter end
The end of a line or chain that is wound around a bitt.
block
One or more pulleys designed to carry a line and change the direction of its travel. A housing around the pulley allows the block to be connected to a spar or to another line. Lines used with a block are known as tackle.
bobstay
A wire from the bowsprit to the stem of a boat, just above thewaterline.
bollard
A large pillar to which a boat's mooring lines may be tied.
boom
A pole securing the bottom of a sail, allowing more control of the position of a sail.
boomkin
A small outrigger over the stern of a boat.
bosun
Also boatswain, bos'n, bo's'n, and bo'sun, all of which are pronounced "bow-sun." A crew member responsible for keeping the hull, rigging and sails in repair.
bosun's chair
A chair, traditionally made from a plank and rope, used to hoist workers aloft to maintain the rigging.
bosun's locker
A locker where tools for maintaining the hull, rigging and sails are kept.
bow
The front of the boat.
bowline
A knot used to make a loop in a line. Easily untied, it is simple and strong. The bowline is used to tie sheets to sails.
bowsprit
Large spar projecting off the front of a boat. A bowsprit allows better positioning of the forestay to maximize use of the jib orgenoa sail.
breakers
A wave that approaches shallow water, causing the wave height to exceed the depth of the water it is in, in effect tripping it. The wave changes from a smooth surge in the water to a cresting wave with water tumbling down the front of it.
breaking seas
With sufficiently strong wind, large waves can form crests even in deep water, causing the wave tops to tumble forward over the waves.
breakwater
A structure built to improve a harbor by sheltering it from waves.
bulwarks
The sides of a boat above the upper deck.
buoy
A floating device used as a navigational aid by marking channels, hazards and prohibited areas.
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