Sailing and Sailboat Glossary - B

Babbitt- A soft white metal alloy frequently used to line replaceable shell type engine bearings; also used in the traversing nut on worm steering.

Back- 1. To sheet a sail to windward and fill the back of the sail and thus stop the boat, or propel it backwards. 2. In case of the wind, to shift counter clockwise from its previous direction.

Backstay- The standing rigging running from the stern to the top of the mast, keeping the mast from falling forward, and can be used to help shape the mainsail.

Backwinded- A sail is backwinded when another sail to leeward of it is trimmed so closely as to cause increased pressure on the lee side of the windward sail thus causing the windward sail to bulge to windward.

Back & Fill- Using forward and reverse gears, as well as an inboard engine’s prop walk and rudder angles, to turn a boat in close quarters.

Bail- 1. To empty the boat of water. 2. A strap attached to the boom at both ends to attach the mainsheet blocks to.

Balance- The capability of a boat to sail straight without changing the tiller position.

Ballast- Weight in the boat for the purpose of providing stability. This weight can be fixed, such as in the keel; or internal such as lead put in the bilge. It can sometimes be considered moveable, such as large crew members that move from side to side.

Bar- A sand, mud or debris shoal, as across the mouth of a river or harbor,

Barber Hauler- A trimming line for positioning the athwartship lead of a jib.

Bare Poles- Under way with no sail set; usually a heavy weather precaution.

Barograph- An aneroid barometer with a specially designed linkage and pen-tipped indicator that makes an ink trace on a clock driven chart.

Barometer- An instrument that measures air pressure, and is considered an aid to forecasting weather.

Batten- A thin wood or fiberglass slat that slides into a pocket in the leech of the sail, helping to maintain an aerodynamic shape.

Batten Down- To secure all hatches and ports in preparation for heavy weather.

Battery- Storage chambers for electricity.

Battery Switch- The main electrical cutoff switch.

Beacon- Anything that serves as a signal or indication for guidance or warning. A fixed (non-floating) aid to navigation.

Beam- The width of the boat at her widest point.

Beam Ends- A boat heeled completely on her side.

Beam Reach- The point of sail where the apparent wind is coming from approximately ninety degrees from the direction of the boat.

Bear Away- To fall off or head away from the wind.

Beam Sea- Sea that is abeam.

Bear Off- Steer away from the wind, shore or object. To steer a new course further off the wind.

Bearing- The direction from one object to another expressed in compass degrees.

Beating- A point of sail towards the direction of the wind. A course sailed upwind.

Beaufort Scale- An arbitrary set of numbers assigned to describe various estimated wind velocities from calm to hurricane force.

Becket- An eye in the end of a block used for securing an end of a line.

Before The Wind- Sailing the same direction the wind blows.

Belay- 1. Secure a line without a knot or hitch. 2. An order to cease action.

Below- The area of the boat beneath the deck. Also an area to leeward of a boat.

Bend- To attach a sail to a spar or a headstay, or to attach a line to a sail.

Berth- 1. The area in which you park your boat; 2. The area in which you sleep on a boat.

Bight- A loop in a line.

Bilge- The lowest part of the boats interior where water on board will collect.

Bimini- A sun awning used to cover the cockpit area.

Binnacle- Pedestal in which a compass is mounted.

Bitt- A perpendicular post through the deck used for securing lines and cables.

Bitter End- The inboard end of the line. The end of the line made fast to the vessel, as opposed to the “working end”, which may be attached to an anchor, cleat or other vessel.

Blanket- The use of a sail or object to block the wind from filling a sail.

Bleeding- The process of purging air from a fuel or hydraulic system.

Block- A pulley on a boat.

Blocking- The effect of a stalled high in slowing or deflecting an eastward moving weather system.

Blooper- A full sail set opposite of the spinnaker.

Boat Hook- A pole with a hook on the end used for grabbing hold of a mooring or retrieving something that has fallen overboard.

Boat Speed- The speed of a boat moving through the water.

Boatswain’s Chair- Seat made fast to a halyard for a person to sit on while working aloft (pronounced Bo ‘sun’s chair).

Bobstay- A stay from the stem to the outer end of a bowsprit.

Bollard- Stout post on a deck, wharf or pier for securing mooring lines.

Boltrope- The rope that is sewn into the foot and luff of some mainsails, and the luff of some jibs by which the sails are attached to the boat.

Boom- The spar extending directly aft from the mast to which the foot of the mainsail is attached’

Boom Vang- A block and tackle system which pulls the boom down to assist sail control.

Boomkin- A spar projecting aft of the stern with a boomkin stay to support the backstay.

Boot Top- A distinctive strip on the exterior of the hull just above the waterline.

Bottom- The underside of a boat.

Bow- The forward part of the boat.

Bow Chocks- Fittings on deck at the bow, through which mooring or anchor lines are led.

Bow line- A line running from the boat of a boat to the dock or mooring.

Bowline- A knot designed to make a loop that will not slip and can be easily untied.

Bowsprit- A spar that extends forward from the bow. Sails and rigging are usually attached to the bowsprit.

Boyle’s Law- The pressure of a gas varies inversely with the volume at a constant temperature.

Breaker- A sea-surface wave that has become too steep to be stable.

Breakwater- A structure, usually stone or concrete, built to create a harbor or improve an existing one.

Breastline- A short line leading directly from the boat to the dock.

Bridle- A length of line or wire rope with both ends secure to the middle of which another line is attached.

Brightwork- Polished metal fittings or varnished woodwork.

British Thermal Unit BTU- The quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit.

Broach- An uncontrolled rounding up into the wind, usually from a downwind point of sail.

Broad Reach- A point of sail in which the boat is sailing in a direction with the wind at the rear corner (the quarter) of the boat. Approximately 135 degrees from the bow of the boat.

Bulkhead- A wall that runs athwartships on a boat, usually providing structural support to the hull.

Buoy- A floating navigational marker.

Buoyancy- The ability of an object to float.

Burdened Vessel- The vessel which must “give way” to another vessel in a crossing or overtaking situation, following the Navigation Rules.

Burgee- A tapered flag with a device denoting a yachting organization.

Buys Ballot’s Law- Used to determine the center of a low-pressure system from wind observations. When you face the wind, the center of low pressure is to your right in the Northern Hemisphere.

By the lee- A sailboat running with the wind coming over the same side of the boat as the boom.