BACK BEARING – A bearing taken on an object behind the vessel


BACKING  - (wind) The changing of the wind direction, opposite of veering. Clockwise in the southern hemisphere, counter-clockwise in the northern hemisphere.


BACKSTAY - Mast support running to aft deck or another mast.


BACKSPLICE - A method of weaving the end of a rope to keep it from unraveling.


BACKSTAFF - A navigation instrument used to measure the apparent height of a landmark whose actual height is known, such as the top of a lighthouse. From this information, the ship's distance from that landmark can be calculated.


BACKSTAY - Wire running from top of mast to stern.


BACKWINDED - When the wind pushes on the wrong side of the sail, causing it to be pushed away from the wind. If the lines holding the sail in place are not released, the boat could become hard to control and heel excessively


BAGGYWRINKLE - chafing gear made from old ropes.


BAIL - Ironrod partially circling the boom to which sheet block is attached 2 To remove water from a boat, as with a bucket or a pump.


BALLAST - Is either pigs of iron, stones, or gravel, which last is called single ballast; and their use is to bring the ship down to her bearings in the water which her provisions and stores will not do. Trim the ballast, that is spread it about, and lay it even, or runs over one side of the hold to the other


BAR - Shallow water usually made of sand or mud, usually running parallel to the shore.


BAR TAUT - Said of a rope when it is under such tension that it is practically rigid.


BAR - Long, low-lying navigational hazard, usually awash, found at river mouths and harbor entrances, where it is composed of sand or mud, and ashore, where it is made of mahogany or some other dark wood. Sailors can be found in large numbers around both.


BARE POLES - Condition of a vessel when she has no sails set.


BARGE - A long, narrow, light boat, employed to carry the principal sea officers, such as admirals and captains of ships of war, to shore.2A long vessel with a flat bottom used to carry freight on rivers. Barges are usually not powered, being pushed or towed by a tugboat instead


BARK - 3 Masted with Square rigged on fore and main mast


BARQUENTINE -3 Masted with Square rigged on fore mast only


BARNACLE - A shellfish often attached to the submerged parts of a vessel.


BAROGRAPH - An instrument used to keep a record of atmospheric pressure, such as on a paper drum


BAROMETRIC PRESSURE - Atmospheric pressure as measured by a barometer.


BARQUE - Sailing vessel with three or more masts: fore and aft rigged on aftermast, square rigged on all others.


BARRATRY - Any wrongful act knowingly done by the master to the detriment of the owner of either ship or cargo; done without knowledge or consent of owner


BATTEN - a short piece of wood or plastic inserted in a sail to keep it taut


BATTEN POCKETS - Pockets in a sail where battens can be placed to stiffen the sail.


BATTEN DOWN - Secure hatches and loose objects both within the hull and on deck.


BEACON - A lighted or unlighted fixed aid to navigation attached directly to the earth's surface.


BEAM - The greatest width of the boat.


BEAM REACH - Sailing 90° to wind.


BEAM SEA – A sea at right angles to a vessel’s course


BEAMS ENDS - Vessel said to be "on her beam ends" when she is lying over so much that her deck beams are nearly vertical. Method used to repair or paint hull before drydocks.


BEAR OFF - To thrust away; to hold off. 2 to steer off wind, shore or approaching object.


BEAR UP - to steer up to the eye of the wind, shore or object.


BEARING - The direction of an object expressed either as a true bearing as shown on the chart, or as a bearing relative to the heading of the boat.


BEARING RING – A ring fitting over a compass and equipped with vanes for observing compass bearings


BEATING - Sailing closehauled, tack upon tack.


BEAUFORT SCALE - A system for estimating wind strengths


BEFORE THE WIND – Sailing with the wind from asterm


BELAY – To change an order.  To make a line secure to a pin, cleat or bitt.


BELAY PIN - Iron or wood pin fitted into railing to secure lines to.


BELOW - Beneath the deck.


BEND - A knot used to join two ropes, lines, cables to one another or to an object, such as an anchor's shackle. A knot, more properly, usually involves untwisting the individual strands of a rope for the purpose of tucking them under and over one another to make a Stopper Knot or a Turk's Head or similar knot.


BEND ON - Attach sail to mast, boom or stay.


BERTH - Any horizontal surface whose total area does not exceed one half of the surface area of an average man at rest, onto which at least one liter of some liquid seeps during any 12-hour period and above which there are not less than 10 kilograms of improperly secured objects.


BETWIXT WIND AND WATER – The part of the vessel at or near the waterline


BIFURCATION BUOY – A buoy marking where a channel divides


BIGHT - The part of the rope or line, between the end and the standing part, on which a knot is formed. BILGE - The interior of the hull below the floor boards.


BILGE - The lowest part of the interior hull below the waterline


BILGE KEEL – A keel fitted at the turn of the bilge where the bottom merges into the side


BILGE PUMP - A mechanical, electrical, or manually operated pump used to remove water from the bilge.


BILL – The tip of an anchor fluke


BIMINII - An awning or canvas that provides shade on deck


BINNACLE - A wooden case or box, which contained compasses, log-glasses, watch-glasses and lights to show the compass at night.


BIRADIAL - Sails in which the panels of cloth radiate from the head and the clew, along the warp.


BITT - A vertically posted above deck used to secure line.


BITTER END - The last part of a rope or chain. The inboard end of the anchor rode.


BLACK GANG - Nautical slang for the engineroom crew. Included the chief engineer, who ran the engine and supervised; oilers and wipers, who lubricated and maintained the engine; and firemen and coal-passers, who fed the steam boilers.


BLANKETED – When a sail is between the wind and another sail, the latter cannot get wind and is said to be blanketed.  One boat can blanket another by sailing between it and the wind


BLOCK - A pulley used to gain mechanical advantage


BLOCK AND TACKLE - A combination of one or more blocks and the associated tackle necessary to give a mechanical advantage.




BOAT - A fairly indefinite term. A waterborne vehicle smaller than a ship. One definition is a small craft carried aboard a ship.


B.O.A.T - Break Out Another Thousand.


BOAT HOOK - A short shaft with a fitting at one end shaped to facilitate use in putting a line over a piling, recovering an object dropped overboard, or in pushing or fending off.


BOBSTAYCABLE - Chain or rod holding down the end of the bowsprit.


BOLT ROPE - A line rope - sewn into the luff of a sail. The bolt rope fits in a notch in the mast or other spar when the sail is raised.


BOLLARD - Vertical post on dock for securing lines. Typically mad of timber or iron.


BOOBY HATCH - Sliding cover that has to be pushed away to allow passage to or from a store room, cabin of small craft, or crew's quarters.


BOOM  - Laterally mounted pole to which a sail is fastened. Often used during jibing to shift crew members to a fixed, horizontal position.


BOOM - a horizontal spar attached to the bottom edge of a sail, riding on the mast and controlled by sheet.


BOOM CROTCH – A board with a notch cut in one end, into which the boom drops


BOOM VANG -Any system used to hold the boom down. This is useful for maintaining proper sail shape, particularly when running or on a broad reach.


BOOT TOP - A painted line that indicates the designed waterline.


BOS'N - Short for Boatswain, pronounced "bosun", the person in charge of the deck crew, and the deck and rigging in general. In the modern Navy the Bos'n is a Warrant Officer, while a Bosn's Mate is a Petty Officer.


BOATSWAIN - Also bosun, bos'n, bo's'n, and bo'sun, all of which are pronounced bosun. A crew member responsible for keeping the hull, rigging and sails in repair


BOUSE - To heave, or haul, downwards on a rope. Originally, and strictly, heave meant an upward pull, haul meant a horizontal pull, bouse meant a downward pull: but these distinctions have not survived.


BOWSE - See Bouse


BOW - The forward part of a boat.


BOW CHOCKS – Metal fittings at the bow, having openings through which an anchor or dock line is passed


BOW LINE - A docking line leading from the bow.


BOW THRUSTER - A small propeller mounted in the bow to push the front sideways.


BOWLINE - A knot used to form a temporary loop in the end of a line.


BOWSPRIT - a long spar attached to the Jibboom in the bow; used to secure head sails.


BRASS HAT - Naval officer with rank of commander or above.


BRASS MONKEY WEATHER - Refers to very cold weather.


BREACH - Said of waves that break over a vessel.


BREAKER - A wave that approaches shallow water, causing the wave height to exceed the depth of the water it is in


BREAST LINE - A line attached laterally from a boat to a dock, preventing movement away from the dock.


BRICKLAYER'S CLERK - A sailor who acts as if he is above it all.


BRIDGE - The location from which a vessel is steered and its speed controlled. "Control Station" is really a more appropriate term for small craft.


BRIDLE - A line or wire secured at both ends in order to distribute a strain between two points.


BRIG - is a two-masted vessel with both masts square rigged. On the sternmost mast, the main mast, there is also a gaff sail


BRIGANTINE - is a two-masted vessel fore mast being square rigged


BRIGHTWORK - Varnished woodwork and/or polished metal.


BROACH - a turning or swinging of the boat that puts the beam of the boat against the waves, creating a danger of swamping or capsizing


BROAD ON THE BEAM – A direction at right angles to the keel


BROAD ON THE BOW – A direction at approximately 45 degrees, port or starboard, from the ship’s head


BROAD ON THE QUARTER– A direction at approximately 135 degrees, port or starboard, from the ship’s head


BROAD REACH - Between beam reach and run


BROADSEAM - A seam in a sail, in which the edges of neighboring panels are cut in a convex curve, so that when they are sewn together the resulting taper in the panels forces fullness into the sail.


BULKHEAD - A vertical partition separating compartments.


BULKWARK - Solid rail along ship side above deck to prevent men and gear from going overboard


BUNG - A round wood plug inserted in hole to cover a nail screw or bolt.


BUNK - a sleeping berth.


BUNTING – Flag material or flags collectively


BURGOO - Seaman's name for oatmeal porridge. First mentioned in Edward Coxere's Adventures by Sea" (1656)


BUOY - An anchored float used for marking a position on the water or a hazard or a shoal and for mooring.


BUOYAGE - The act of placing buoys. 2. Establishment of buoys and buoyage systems. Applied collectively to buoys placed or established.


BUOYANCY - Degree of floatability

BURDENED VESSEL - That vessel which, according to the applicable Navigation Rules, must give way to the privileged vessel. The term has been superseded by the term "give-way".


BURDENED VESSEL - The boat which, in a collision situation, did not have the right-of-way. See Privileged Vessel.


BURGEE - A type of flag used to identify a boater's affiliation


BUTTY - A non powered boat usually a narrow boat, being towed by one with an engine.


BY THE BOARD - Overboard and by the ship's side.


BY THE HEAD - Bow lower then stern.


BY THE LEE – Sailing before the wind, with the wind coming from the same side the boom is on.  Dangerous because it can result in an accidental gybe.


BY THE STERN - Stern lower then bow


BY THE WIND - Close hauled to wind