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Nautical Glossary

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Nautical Glossary

Nautical Glossary  
By  
Richard J. Nikas

Abaft - Toward the stern.
Abaft the Beam - Any direction between either beam and the stern.
Abandon Ship – To leave the ship in an emergency.
Abeam – At right angles to the keel.
Able Seaman – Merchant marine rating above ordinary seaman. Also known as able bodied seaman, from which the term AB is derived.
Aboard – On or in a ship.
Abreast – Side by side. By the side of any object aboard ship.
Accommodation Ladder – A flight of steps shipped to a platform at the ship’s gangway and extending nearly to the water’s edge.
Adrift – Floating at random. Unfastened or loose.
Affreight – To hire for the purposes of transporting freight.
Afloat – Supported by the water.
Afore – Forward.
Aft – Near or toward the stern of a vessel.
After Body – That portion of a ship’s body aft of the midship section.
After Frames – Frames aft of amidships, or frames near the stern of the ship.
After Peak – A compartment immediately forward of the stern post. Generally situated entirely below the load waterline.
Aground – Wholly or partially resting on the bottom.
All Hands – All those aboard ship.
All Night In – A full night’s sleep with no watch.
Aloft – Above the decks.
Alongside – Near the side of the ship.
Amidships – In the vicinity of the middle portion of a vessel as distinguished from her ends.
Anchor – A heavy iron or steel implement attached to a vessel by means of a rope or chain cable for holding it at rest in the water. When an anchor is lowered to the bottom, the drag on the cable causes on or more of the prongs, called flukes, to sink into or engage the ground which provides holding power.
Anchorage – A customary, suitable and designated harbor area in which vessels may anchor.
Anchorage Buoy – Buoy marking limit of an anchorage area.
Anchor Light – A white light at the mast top displayed while anchored.
Anchor Rode – The line or chain attached to the anchor.
Anchor Watch – One, two, or more men detailed to look after the vessel while at anchor or in port.
Apeak – When the anchor chain is hove taught so as to bring the vessel over her anchor.
Apogee – The point farthest from the earth in the orbit of the moon.
Apparel – Equipment and fittings of a ship that are removable.
Apparent Wind – The direction and force of the wind relative to a moving vessel, differing from true wind.
Apron – Area of a pier or wharf on which cargo is unloaded.
Ardent – Said of a sailing vessel if her head tends to come up into the wind when sailing close hauled.
Aspect Ratio – The ratio between the width and height of a triangle.
Ashore – On the beach or shore.
Astern – In the direction of the stern.
Athwart – At right angles to the centerline.
Athwartships – Reaching across a vessel from side to side.
Atrip – The position of the anchor when it is raised clear of the ground.
Avast – Order to stop or cease.
Awash – So low that water washes over.
Aweigh – The position of an anchor when it is raised clear of the ground. The same as Atrip.
Awning – A canvas canopy spread over a vessel’s decks, bridges, etc., for protection against rain and sun.
Aye – Yes. I have heard and understand.
Aye Aye – A seamanlike response to an order or instruction signifying that the order is heard, understood, and will be carried out.
Azimuth – The horizontal angle between the reference point and an object.
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Back – To reverse engines so that a ship may be stopped or made to go astern.
Backrush – The flow of water down the foreshore after the uprush of incoming waves.
Backstay – Piece of standing rigging leading aft. Stays which extend from all mast levels, except the lower, to the ship’s side some distance abaft the mast. They serve as additional supports to prevent the mast from going forward, and at the same time contribute to the lateral support, thereby assisting the shrouds.
Backwash – Water thrown aft by the turning of the propeller.
Bail – To dip water out of a boat.
Ballast – Any weight carried solely for the purpose of making the vessel more seaworthy. Ballast may be either portable or fixed, depending upon the condition of the ship. Permanent ballast in the form of sand, concrete, scrap or pig iron is usually fitted to overcome an inherent defect in stability or trim due to faulty design or changed character of service. Portable ballast, usually in the form of water pumped into or out of bottom, peak or wing ballast tanks, is utilized to overcome a temporary defect in stability or trim due to faulty loading, damage, etc.
Bank – An elevation in the sea’s bottom which, if of sufficient height forms a shoal.
Bar – A shoal comprised of sand, mud or debris, often across the mouth of a river or harbor.
Bare Boat Charter – Lease of a ship without equipment or crew.
Barge – A floating craft of full body and heavy construction, designed for the carriage of cargo, but without means of self-propulsion. The distinction between a barge and a lighter is more in the manner of use with the term barge being more often used when the load is carried to its destination, or a long distance, while the term lighter refers to a short haul, generally in connection with the loading or unloading operations of vessels.
Bark – A vessel having three masts, fore, main and mizzen. The two forward are square rigged and the after or mizzen is fore-and-aft rigged.
Barkentine – A vessel having three masts, fore, main and mizzen. The fore mast is square rigged and the main and mizzen fore-and-aft rigged.
Barnacle – A crustacean which adheres in clusters to the underwater portion of vessels, piles, piers, etc.
Barometer – An instrument for measuring the weight or pressure of the air. It indicates whether the pressure is becoming greater or less, or remaining stationary (atmospheric pressure). There are two kinds of barometers, the aneroid and the mercurial. The barometer is read in inches, two inches representing about one pound of atmospheric pressure.
Barratry – A fraudulent breach of duty or a willful act of known illegality on the part of the master of a ship, in his character of master, or of the crew, to the injury of the owner of the ship or cargo aboard without his consent.
Batten – A narrow strip of wood or plastic used to stiffen the leach of a sail.
Batten Down – To cover and fasten down.
Battening Down – Making the hatches watertight by firmly secured tarpaulins to the hatch coamings with battens, wedges, etc.
Beacon – A lighted navigational aid.
Beam – The extreme width of a vessel. A transverse, horizontal member supporting a deck or flat.
Beam Reach – A point of sailing with the apparent wind blowing at right angles to the boat’s centerline.
Bearing – The direction of an object from the person looking as indicated by degrees of the compass. A block on or in which a journal or shaft rotates; a bearing block.
Bear Off – To turn away from the wind.
Beating – Sailing against the wind on alternate tacks.
Becket – An eye for securing one end of a line to a block.
Before the Wind – Said of a sailing vessel when the wind approaches from the aft over the stern.
Belay – To secure a rope or line about a cleat or belaying pin by winding it back and forth in the manner of the figure eight.
Belaying Pin – A long, round metal rod used for securing lines.
Belly – The cantenary of a tow line or the bulging part of a sail which holds the wind.
Below – Beneath or under the deck.
Bend – The act of securing one thing to another.
Berm – The nearly horizontal formation along the beach caused by the material deposited by waves.
Berth – [1] Anchorage or mooring space assigned a vessel. [2] Sleeping place assigned a man on board ship. [3] The margin by which a vessel is passed.
Between Decks – A term applied to the space between any continuous decks.
Between the Devil and the Deep Blue Sea – Adage used to describe situation where on is left with no choice.
Between Wind and Water – Refers to that part of a ship just at the waterline which is alternately exposed and underwater as the ship heels and rolls.
Bight – A loop or bend in a rope; though, strictly considered, any part between the two ends may be termed the bight.
Bilge – The rounded portion of a vessel’s shell which connects the bottom with the sides. To open a vessel’s lower body to the sea. The yellowing of white paint.
Bilge Keel – A strake on the outside of a hull to reduce rolling.
Bilge Pump – Pump used to clear the bilge of water.
Bilge Water – Drainage water which accumulates either in the bottom or the bilge.
Bill – The point at the extremity of an anchor fluke.
Billet – An assignment of quarters aboard ship. Duties, tasks, and responsibilities performed by one person.
Bind – To secure the end of a rope against unlaying by taking turns of twine or small-stuff around it. The term is synonymous with whip.
Binnacle – The stand or support for a magnetic compass.
Bioluminescence – The emission of visible light by living organisms.
Bitter End – The absolute end of a piece of line or cable.
Bitts – Pair of short steel posts or horns on board ship used to secure lines.
Black gang – The fireroom force (fireman and coal passers on a coal-burning vessel).
Blast – Signal on a ship’s whistle.
Blip – Echo as recorded on a radar screen.
Block – A name given to a pulley or sheave or system of pulleys or sheaves mounted in a frame or shell, for the purpose of moving objects by means of ropes run over the pulleys or sheaves.
Boarding – The act of going on board a ship.
Boat – A small craft usually capable of being hoisted aboard a ship.
Boat Harbor – A protected water area in a harbor equipped with mooring floats, buoys, etc., for mooring small boats, yachts, etc.
Boat Hook – A hook on a pole used for retrieving or picking up objects and for fending the vessel off the quay.
Boat Plug – Threaded drain plug fitting in the bilge of a boat.
Boat Stowage – The provisions made aboard a ship for stowing and launching lifeboats.
Boatswain – The ranking chief petty officer who has immediate charge of the deck and boat seamanship pronounced as bosun.
Boatswain’s Chair – Seat sent aloft or over the side on a line to facilitate repairs or painting.
Boiler – Metal chamber in which steam is generated.
Bollard – Steel or iron post on a dock, pier, or wharf, used in securing a ship’s lines.
Booby Hatch – A raised small hatch.
Boom – A term applied to a spar used in handling cargo, or as the lower piece of a fore-and-aft sail.
Boom Mounting – All metal bands, collars and other gear secured to a boom to connect it to a mast or for attaching ropes to the boom.
Boom Vang – A system of fittings used to hold down under certain sailing conditions.
Bottomry – The business of leasing or mortgaging ships.
Bossing Plate – Steel plate covering the bulged portion of hull where the propeller shaft passes outboard.
Bosun’s Chair – A seat used to hoist a person aloft to repair rigging or tend to the vessel.
Bosun’s Locker – A shipboard storage area for deck supplies, paint, rigging fittings and tools.
Bow – The sides of a vessel at and for some distance abaft the stern, designated as the right-hand, or starboard bow, and the left-hand, or port bow.
Bow Line – A mooring or dock line at the bow.
Bowline – A classic knot that forms a loop that will not slip nor become tighter under tension.
Bow Plating – A term applied to the shell plating in the bow of a vessel.
Bow Rope – A rope leading from a vessel’s bow to another vessel or to a wharf for the purpose of hauling her ahead or securing her. Also known as a bowline or bow-fast.
Bowsprit – A built-in spar projecting forward and slightly up from the bow of a sailing vessel. It extends beyond the head sails and helps support the mast(s) through headstays.
Box the Compass – To name all points of a compass in succession.
Brackish – A mixture of fresh and seawater.
Breast – To meet the waves bow on.
Breast Lines – A mooring line from the ship to the pier which holds the ship in.
Breakbulk Cargo – General cargo handled item by item as distinct from containerized cargo.
Break Ground – To weigh the anchor and lift it out of the bottom.
Break Out – Take out of stock or storage. To prepare for use.
Breakwater – A term applied to plates fitted on a forward weather deck to form a barrier against water that is shipped over the bow.
Breeches Buoy – A lifesaving contrivance for rescuing persons from a wreck.
Bridge House – A term applied to an erection or superstructure fitted about amidship on the upper deck of a ship.
Bridle – A bridle may be described as wire, steel or manila hangers that resemble an inverted “V”. They are used to sling an object by two or more points to keep it trim when handling.
Brig – A vessel having two masts, fore and main. Both of these are square rigged, but the main mast has in addition a gaff mainsail. A cell for the confinement of a person undergoing punishment or placed therein for safekeeping.
Bristol Fashion – Shipshape. Conforming to the highest standards of seamanship.
Broach – To break the surface of the water with the hull in an explosive manner or to come broadside to the sea while heeling at an extreme angle.
Broad on the Beam – At a right angle to a vessel.
Broad Reach – A point of sailing with the apparent wind broad on the beam.
Broadside – In a direction parallel to the side of the ship.
Broken Stowage – Wasted space in a ship’s hold. Small packages are used to fill such hold space.
Broken Water – An area of small waves and eddies in otherwise calm water.
Brought Up – Said of a vessel when she is stopped but not at anchor.
Buckle – A distortion, such as a bulge.
Bulk Cargo – Cargo made up of commodities such as oil, coal, water, grain, etc.
Bulkhead – A term applied to any of the partition walls used for subdividing the interior of a ship into the various compartments.
Bullnose – Closed chock at the bow of a vessel. Has the appearance of a large flared nostril.
Bulwark – A term applied to the strake of shell plating or the side planking above a weather deck. It helps to keep the deck dry and also serves as a guard against losing deck cargo or men overboard.
Bunk – Bed on board a ship.
Bunkers – The fuel oil burned by a ship.
Bunkering – The operation of conveying fuel to a vessel.
Bunt – The middle of a sail.
Buoy – A term applied to a floating object that is moored or anchored so that it remains at one place indicating a position on the water, an obstruction or shallow area, or to provide a mooring for a ship.
Burdened Vessel – The vessel required to take action to avoid collision under the Rules of the Road.
Burgee – A triangular or swallow-tailed pennant, bearing either the name of the vessel or the device of the company or firm owning or operating the vessel.
Buttocks – The rear end of a vessel.
By the Head – Said of a vessel when her head is lower in the water than her stern.
By the Stern – Said of a vessel when her stern is lower in the water than her head.
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Cabin – Compartment used as living quarters aboard ship.
Cable – A heavy, large line used for mooring or towing large vessels.
Cable Length – A cable length is 120 fathoms.
Camber – The athwartship curvature of a deck.
Can – A cylindrical buoy, usually green.
Cant – The inclination of an object from the perpendicular.
Cantilever – A projecting beam supported at only one end.
Cantline – The groove between the strands of a rope.
Cap – The proper term for the top of a mast except or the highest mast where it is called a truck.
Capacity Plan – Plan of a vessel displaying the capacities of its holds, tanks, and other cargo carrying spaces.
Capsize – To turn over.
Capstan – The rotating mechanism that actually raises the anchor or other heavy weight.
Cardinal Point – One of the four principal points of the compass.
Careen – To incline from the upright, whether done by wind and sea or mechanically for the purpose of making repairs.
Cargo – Merchandise or goods accepted for the transportation by the ship.
Cargo Net – Square net of heavy line used to lift cargo in loading or unloading operations.
Cargo Plan – Plan showing the capacity of each of a ship’s holds.
Cargo Port – Opening in a vessel’s side through which cargo can be loaded.
Cargo Whip – Rope or chain used with a derrick and winch for handling cargo.
Carling – Short support between beams.
Carry Away – Tear or break loose; break; part; wash away. To break a spar or part a piece of rigging.
Carry On – An order to resume or continue previous activity.
Castaway – A man from a wrecked ship.
Cast Loose – To let go a line or lines.
Cast Off – Order given to let go or throw off mooring lines.
Catenary – The dip in a length of chain or cable due to its own weight. The catenary provides spring or elastic effect in towing, anchoring or in securing to a buoy.
Catfall – Part of the anchor gear. A small tackle used to hoist an old-fashioned anchor from the water to the cathead on weighing anchor.
Catwalk – A walkway constructed over or around obstructions on a ship for convenience of the crew.
Caulk – To fill the gap between planks.
Cavitation – Turbulence in the water caused by the rotation of a propeller.
Celestial Navigation – Determining position by observation of celestial bodies.
Centerline – An imaginary line down the middle of the ship from stem to stern.
Center of Gravity – The point at which the combined weight of all the individual items going to make up a vessel’s total weight may be considered as concentrated.
Center of Pressure – The point in a sail or an immersed plane surface at which the resultant of the combined pressure forces acts.
Chafing Gear – Material used to prevent chafing or wearing of sails, line, etc.
Chafing Plate – A plate worked around the lower edges of hatch beams or carlines to prevent wear on the hoisting ropes. Also applied to plates fitted on the forecastle deck under the anchor chains.
Chain Locker – Compartment where anchor chain is stowed.
Chain Stopper – A device used to secure the chain cable when riding at anchor, thereby relieving the strain on the windlass, and also for securing an anchor in the housing position in the hawse pipe.
Chandlery – Items of nautical gear or the store where such items are sold.
Channel – The navigable portion of a waterway.
Chanty – A song of simple lyrics and tune sung by men at sea.
Charley Noble – A protective cap for the smoke pipe from the galley.
Chart – Nautical map.
Charthouse – Compartment on or near the bridge for handling and stowage of navigational equipment.
Check – To keep a strain on a line but to ease it out to prevent parting. Slow.
Chine – The line formed by the intersection of side and bottom in ships having straight or slightly curved frames.
Chock – Metal fitting through which hawsers and lines are passed.
Chronometer – An accurate navigational clock.
Clap On – To clap on a rope means to catch hold in order to haul on it.
Classification – Certification by a classification society as to the character of construction and outfitting of the vessel classed.
Cleat – A wood or a metal fitting having two projecting arms or horns for securing or belaying lines.
Clew – The sail corner between the leech and foot.
Clinch – The end of a rope half-hitched around the standing part and stopped.
Clipper – General name for a fast sailing ship.
Close Aboard – Near.
Close Hauled – Sailing as close as possible to the wind.
Clove Hitch – A knot much used for fastening a line to a spar or stanchion.
Coaming – Raised framework around deck or bulkhead openings and cockpits of open boats to prevent entry of water.
Cofferdam – Void or empty space separating two or more compartments for the purposes of insulation, or to prevent the liquid contents of one compartment from entering another in the event of the failure of the walls of one to retain their tightness.
Coiling – Method of stowing a rope by winding it round in the direction appropriate to its lay.
Collision Bulkhead – The foremost main transverse watertight bulkhead.
Collision Mat – A mat of canvas and fiber designed to be hauled down over the hole in a ship’s hull caused by a collision.
Come About – To change direction so that the wind is coming over the other side.
Companion – The cover over a companionway.
Companionway – A hatch or opening in a flat deck or house top to provide access; principally for the personnel.
Compartment – A subdivision of space or room in a ship.
Compass – Instrument for determining direction on a vessel.
Compass Card – A circular card in a compass that is marked with the cardinal points, intercardinal points, and the others in between. The compass card appears to rotate, but it is the ship that rotates around the card.
Compass Error – Total difference between compass heading and true heading.
Compass Rose – An outer and two inner graduated circles printed in several places on a nautical chart to assist in recording bearings and laying courses.
Conn – Control of ship’s movements.
Cordage – A term that includes all rope and small line whether made of natural or synthetic fibers.
Corinthian – An amateur yachtsman.
Counter – That part of a ship’s stern which overhangs the stern post, usually that part above the water line.
Counter Flood – To take water into a ship’s tanks or compartments to reduce list or inclination by bow or stern.
Course – Direction in which the vessel is steered.
Course Recorder – An instrument, operated electrically from the master compass that makes a permanent record of the exact courses steered.
Coxswain – A petty officer or sailor who steers or has charge of a small boat.
Crab – To move sidewise through the water.
Cradle – A frame used to support a vessel on land.
Cringle – A grommet used to prevent chaffing by an attached line.
Crosstrees – A term applied to athwartship pieces fitted over the trees on a mast. They serve as a foundation for a platform at the top of a mast or as a support for outriggers.
Crown – Term sometimes used denoting the round up or camber of a deck. The crown of an anchor is located where the arms are welded to the shank.
Cuddy – Cabin in the foreward part of a vessel.
Current – Horizontal movement of water.
Current Direction – The compass heading toward which water moves.
Cusp – Sand deposited, by wave action, in the form of points or bars projecting seaward along a beach.
Cut and Run – To depart hurriedly.
Cut of the Jib – General appearance of a vessel or of a person.
Cutwater – A timber bolted to the forward side of the stern in wooden ships. The forward edge of the stern in steel vessels is also called a cutwater.
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Davit – A crane used to lower and raise lifeboats and sometimes anchors.
Davy Jones – The spirit of the sea.
Davy Jones’ Locker – A common phrase of sailors, applied to the bottom of the ocean as the grave of all who are drowned or perish at sea.
Dead Center – Those points during the stroke of a reciprocating engine at which the line of action of the connecting rod and the axis of the crankshaft lie in the same plane.
Dead Eye – A solid oblate or flat circular piece of hard wood having three holes for reaving a lanyard in setting up the standing rigging.
Dead Head – Log floating on end and mostly submerged.
Dead in the Water – Said of a vessel that has stopped and has no way on, but is not moored or anchored, nor is in any way fast to the ground or a pier.
Dead Light – A porthole which does not open.
Dead Man – Timber or similar object buried in ice or in the ground to secure guys, tackles, or a ship’s lines.
Dead Rise – The angle which the straight portion of the bottom of the floor of the midship section makes with the base line. It is expressed by the number of inches rise above the base line in the half-beam of the vessel.
Dead Reckoning – The navigation means used to determine position, calculated from the course steered and the speed through the water, without obtaining a fix.
Dead Ship – One without power.
Deadrise – Vertical distance between a vessel’s keel and the turn of the bulge.
Decca – Medium-frequency continuous-wave radio navigation system. For precise positioning within short range of transmitters.
Deck – A floor on a ship.
Deck Hand – A man who works topside, on deck, usually a seaman.
Deck Log – Record of the vessel and her voyages kept by the officer of the watch.
Derelict – Abandoned vessel at sea, still afloat.
Detritus – Accumulation on the sea bottom of rocks or rock particles and of broken organic material.
Devil’s Claws – a device having two heavy claws designed to fit over a link in the anchor chain for the purpose of securing the anchor and chain in the desired position.
Dinghy – A small boat used as a tender.
Dip the Eye – To arrange the eyes of secured mooring lines in such a manner that either line may be removed without disturbing the other.
Dip a Light – To sail away from a navigational beacon so that it falls below the horizon.
Discharge – To unload cargo from a vessel.
Displacement – The weight of water displaced by a floating vessel.
Displacement Hull – A boat supported by its own buoyancy while in motion.
Ditty Bag – A small bag for the tools and personal items.
Diurnal – Recurring daily.
Dividers – Instrument for measuring off distance on a chart. Much used by the navigator in determining courses and distances.
Dock – Strictly speaking, the water-space alongside a wharf, pier, quay or between two wharfs or piers, in which a ship floats while being loaded or unloaded.
Dog Watch – A watch of two hours so as to change the regular four hour watches stood from day to day by the officers and each division of the crew. The first dog watch is from 1600 to 1800 while the second is from 1800 to 2000.
Doldrums – Those parts of the sea where calms are known to prevail. Also applied to a person in low spirits.
Dolphin – A term applied to several piles that are bound together, situated either at the corner of a pier or out in the stream and used for docking and warping vessel. Also applied to single piles and bollards on piers that are used for docking and warping.
Double Up – To double mooring lines for added security.
Douse – To lower or put out quickly.
Downhaul – Line or wire which pulls or leads downward.
Downwind – A direction to leeward, with the wind.
Draft – The vertical distance from keel to waterline. The minimum depth of water which a vessel requires to remain afloat.
Drogue – A sea anchor.
Drydock – A hauling out place from which the water can be drained for cleaning or repair.
Dunnage – Loose material placed around cargo to prevent motion or chafing.
Dutch Courage – Courage obtained from alcohol.
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Ease – Relax a strain.
Easy – Carefully.
Ebb – Period when the tidal current flows from land.
Eddy – A circular motion in the water caused by the meeting of opposite currents.
Electrolysis – The decomposition of metal by an electric current.
El Nino – A meandering, westward dislocation of the Humboldt Current off the west coast of South America  
End On – Said of a vessel when only her bow can be seen.
Entrance – The portion of the bow which cuts the water.
EPIRB – Emergency Position Indicating Radio Beacon. A small continuously operating transmitter used to alert authorities of an emergency and provide the location of the vessel in need of assistance.
Escutcheon – The place on the stern of a ship where her name and port of registry are inscribed.
Estimated Position – The navigational position determined from estimates rather than from known data.
Even Keel – Floating evenly and level without list.
Eye Splice – A fixed loop in the end of a line.
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Fairleader – A term applied to fittings or devices used in preserving the direction of a rope, chain or wire so that it may be delivered fairly or on a straight lead to the sheave, drum, etc.
Fair Wind – A favoring wind.
Fake – To lay a rope or chain down in long bights side by side or in coils in regular order, so that it will run out clear or can be easily and rapidly paid out. One complete circle of a coil of rope.
Fall Foul Of – To be obstructed by another vessel.
Fall In With – To meet another vessel by chance.
Fall Off – Said of a ship or the bow of a ship when it drifts away from a desired position or direction.
Falls – The ropes by which a boat is lowered and hoisted by davits.
Fantail – The aftermost deck area topside in a ship.
Fast – Snugly secured.
Fathom – Measure of length which is equal to six feet.
Fathometer – Another name for an echo sounder.
Feather – To turn the blade of an oar horizontally at the finish of a stroke to reduce resistance of air or water.
Feel the Way – To proceed cautiously, taking soundings with the lead.
Fender – A device of canvas, wood, line, cork, rubber, wicker or plastic slung over the side of a ship in position to absorb the shock of contact between ships or between a ship and pier.
Fend Off – To push away. To prevent a ship or boat from coming into contact with another vessel or structure.
Fid – A tapered pin like tool used to separate the strands when splicing rope.
Fill – To adjust a vessel’s sails so that the wind may force her ahead.
Fine Trim – In the best of spirits.
Fitting – Generic term for any part or piece of machinery or installed equipment.
Fix – A navigational position determined from terrestrial, electronic or astronomical data.
Flake Out – Slang meaning to lie down.
Flange – The turned edge of a shape or girder which acts to resist a bending movement.
Flank Speed – Maximum speed.
Flare – The curve of a vessel’s bows both upward and outward.
Flaw – Sudden gust of wind.
Flemish – To coil a line laid flat on deck in a spiral fashion.
Flinders Bar – Iron bar inserted in the binnacle of a magnetic compass to help compensate for deviation.
Flood – Period when the tidal current flow toward land.
Floor – The inside bottom of a hull.
Flotsam – Wreckage or debris afloat on the water.
Flukes – The palms or broad holding portions at the arm extremities of an anchor, which penetrate the ground.
Flying Bridge – Topmost bridge of a ship, usually above the navigating bridge or conning tower.
Fore and Aft – From stem to stern.
Forecastle – A superstructure fitted at the extreme forward end of the main deck.
Foredeck – The forward part of the main deck of a vessel.
Forepeak – The extreme forward compartment of a vessel.
Forestay – A stay supporting a mast from forward.
Forward – In the direction of the stern.
Foul – To entangle, confuse or obstruct. The underwater portion of the outside of a vessel’s shell when it is more or less covered with barnacles, grass or foreign matter.
Foul Anchor – Anchor entangled in its chain or for any other reason not clear for hoisting all the way up.
Foul Ground – Shallow sea area marked by rocks, reefs, shoals, wrecks, etc.
Foul Hawse – To have a foul hawse means there is an obstruction or potential obstruction in the hawse hole preventing normal heaving in.
Fouling – The attachment of various marine organisms to underwater bodies, a problem in ships because it reduces speed.
Foul Up – Slang for getting into trouble.
Foul Weather – Rainy or stormy weather.
Founder – To sink.
Frame – A term generally used to designate one of the transverse ribs that make up the skeleton of a ship.
Frap – To frap is to wrap with line.
Frapping Lines – Lines passed around forward and after boat falls to steady the boat in a seaway as it is being hoisted or lowered.
Free – To clear or untangle.
Freeboard – Distance from the weather deck to the waterline.  
Freshen the Nip – To change the position of a rope that is being chafed.
Full and By – The order given to keep the sails full and at the same time close to the wind.
Full and Down – Said of a ship when all spaces are full of cargo and ship is down to maximum specified draft and drag.
Furl – To bundle and secure.
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Galley – A kitchen on a vessel.
Gang – A detachment of men selected for some particular service.
Gangplank – A runway or board fitted with wooden cleats for the use of persons boarding and leaving a vessel. It is also a runway for the trucks engaged in side-port loading and discharging.
Gangway – The aperture in a ships’ side for the accommodation of persons entering and leaving.
Gantline – Line passing through a single block aloft.
Garboard Strake – The plank just above the keel.
Gather Way – To begin to move through the water.
Ghosting – Sailing on a wind of minimum force.
Gilligan Hitch – Any unseamanlike, unorthodox, knot, hitch or bend.
Gimbals – A device by which a ship’s compass, chronometer, etc., are suspended in a constant horizontal position irrespective of the rolling and pitching of the vessel.
Gipsy – An auxiliary drum on a windless or capstan used for handling lines.
Girth – The measurement around the body of a ship.
Give Way – To allow another vessel the right of way.
Gloryhole –A place for hiding prized possessions.
GPS – Global Positioning Satellite. Term used to describe method of electronic navigation which uses satellites for triangulation to fix the position of a vessel.
Grapnel – A clawed hook used for retrieving article from the bottom.
Grave – To clean a ship’s bottom while in a dry dock.
Great Circle – The intersection of the earth’s surface and a plane through the earth’s center. The shortest route between two points on the surface of the earth.
Grommet – Reinforced hole in a sail or awning.
Gross Tonnage – The total interior space of a ship including non-cargo space.
Ground Swell – A swell that becomes shorter and steeper as it nears shore.
Ground Tackle – A general term for all anchors, cables, buoys, ropes, purchases, etc., used in the operation of mooring and unmooring a ship.
Gudgeons – Eyes set in the stern or the rudder post which receive the pintels of the rudder.
Gunwale – A term applied to the line where a weather deck stringer intersects the shell.
Guy Pendant – A pendant that connects the head of a boom with a guy tackle and serves to shorten the length of the guy tackle. Some guy pendants are fitted with swivels at each end for the purpose of keeping the guy tackle free of turns.
Guys – Wire or hemp ropes or chains which support booms, davits, etc., laterally.
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Hack Watch – A good watch with a second hand, used in taking observations to obviate the necessity of constantly moving the chronometer.
Hail – A call to a ship or boat.
Half Shot – Almost drunk.
Halyard – A line used to hoist a sail or spar aloft.
Hand Lead – Weight and line used in taking soundings.
Handsomely – Slowly and carefully in a proper manner.
Hanging Locker – A storage place for clothing.
Hard Alee – A warning that the helmsman is going to put the ship about.
Hard Over – All the way in one direction. Usually describes the state of the tiller or wheel on an abrupt turn.
Hatch – An opening in a deck giving access below.
Hatch Beam – Steel support for a cargo hatch cover.
Hatch Coaming – Raised framework around a hatch on which the hatch cover rests.
Hatch Cleat – A term applied to the clips attached to the outside of the hatch coamings for the purpose of holding the hatch battens and edges of the tarpaulin covers.
Hatch Cover – Wooden or steel cover for a hatch.
Hawse – Area at bow of ship where hawsepipes are located.
Hawsepipes – Heavy casting through which the anchor chain runs from deck down and forward through ship’s bow plating.
Hawser – A large diameter rope used for towing and mooring lines on larger vessels.
Haze – Punishing a man by keeping him unnecessarily at some disagreeable work.
Head – The toilet on board a vessel.
Head Board – Foremost bulkhead within a vessel.
Head Line – Mooring line that is made fast forward of the ship’s pivot point.
Head Seas – Waves coming from the direction a vessel is heading.
Head Stay – Wire support from top of forward mast to bowsprit of a sailing vessel.
Heading – The direction in which a vessel is pointed.
Heave – To haul in or throw off. The alternate rising and falling of a vessel in a seaway.
Heave In – To haul in.
Heaving Line – A small line bent to a hawser, the loose end thrown ashore and caught for the purpose of hauling one end of the hawser to the wharf for making fast.
Heel – The inclination of a ship to one side.
Helm – The helm proper is the tiller, and thus the order to put the helm to port, for example, is the same as an order to put the rudder right. Because of possible confusion as to intended direction, however, helm orders are given with respect to the rudder, and never with respect to the helm, using right and left, never starboard and port.
Helmsman – Person charged with steering a vessel.
High Seas – The enclosed waters of the ocean outside the boundaries of a country.
Hitch – A knot whose loops jam together in use, particularly under strain, yet remain easily separable when the strain is removed.
Hogging – Straining of the ship that tends to make the bow and stern lower than the middle portion.
Hoist – To raise or elevate by man power or by the employment of mechanical appliances.
Hold On – To keep a vessel to her course.
Holds – The large spaces below the deck for the stowage for the cargo.
Holystone – Small stone used with sand and water to scrub wooden decks.
Home – The port from which a vessel hails.
Homeward Bound – Said of a vessel when heading back to her home port.
Hood – A shelter over a companionway.
Horizon – the line where sea and sky appear to meet.
Horse Latitudes – A belt of calms and light airs in the North Atlantic which borders the northern edge of the North East trade winds.
Hove Taut – Pulled tight.
Hull – The structural body of a ship.
Hull Speed – The maximum practical speed of a displacement hull of given length.
Hunt – To oscillate about a midpoint.
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In Step – The condition of a tug and tow when both meet and ride the seas at the same time.
Inboard – Towards the center.
Inshore – Towards land.
Irish Pennant – The frayed loose end of a line.
Irons – Unable to maneuver.
Isobar – a line connecting points of equal barometric pressure.
Isogon – A line connecting points with the same magnetic variation.
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Jackass – Cover over hawespipe to keep water out.
Jackstaff – A term applied to a flag pole erected in the bow of the vessel.
Jack Ladder – Ladder with rope sides and wooden rungs.
Jacob’s Ladder – Portable ladder, with rope or wire sides and wooden rungs, slung over the side for temporary use.
Jammed – Wedged tight.
Jaw – Insolent talk to a superior.
Jetsam – Material thrown overboard.
Jetty – A structure which projects from the shore.
Jew’s Harp – Ring or shackle at upper end of shank of an anchor to which anchor chain is secured.
Jigger – Light luff tackle used generally about the deck.
Judas – Any rope hanging down unfastened and unprotected from the wind.
Jury – A term applied to temporary structures used in an emergency.
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Kedge – A small anchor generally used for freeing a grounded vessel.
Keel – A center line strength member running fore and aft along the bottom of a ship and often referred to as the back bone.
Keelhaul – Slang term meaning to reprimand severely. To scrub the bottom of a wooden vessel.
Keelson – A timber placed inside over the keel.
Kelter – In good condition.
Kevel – A mooring post or cleat on which to fasten mooring lines.
Knot – Unit of speed equivalent to one nautical mile per hour.
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Labor – A vessel is said to labor when she rolls or pitches heavily.
Landfall – The sighting of land from a vessel at sea. Reaching the coast.
Landlubber – Seaman’s term of derision for one who has never been to sea, hence a lubber, or lubberly.
Land Shark – Lawyer.
Lanyard – A length of rope or cord used in numerous dissimilar ways. Any line having a loose end the other being attached to any object for the purpose of either near or remote control.
Lapstrake – A term applied to boats built on the clinker system in which the strakes overlap each other.
Larboard Side of a Ship – The left hand side of a ship looking forward.
Lash – To secure with line or wire by wrapping and tying with seamanlike knots in the case of line, or with an approved hitch in the case of wire.
Latitude – The measure of angular distance in degrees, minutes and seconds of arc from 0 degrees to 90 degrees north or south of the equator.
Launch – To put a vessel into the water. A small open powerboat used for transportation between a vessel and shore.
Lay – Direction in which strands are twisted to form various types of rope.
Lazaret – Storage compartment in the stern of a ship or boat.
Lee – The side opposite to that from which the wind blows.
Leech – Trailing edge of a fore and aft sail.
Left Handed – Counterclockwise.
Leg – One section of a span or bridle.
Length Between Perpendiculars – The length of a ship measured from the forward side of the stern to the aft side of the stern post at the height of the designated water line.
Levee – An embankment to prevent inundation.
Lie Off – To remain stopped a short distance away.
Lifeboat – A boat carried by a ship for use in an emergency.
Lifting Gear – Term used to describe the cranes, derricks, and attached equipment used for the handling of cargo.
Light – Said of a vessel when she is not carrying her full capacity of cargo.
Lightening Hole – A hole cut in a structural member to reduce its weight.
Lighter – Barge –like vessel used to load or unload ships.
Limber Hole – A hole or slot in a frame or plate for the purpose of preventing water from collecting.
Line – A general term for a rope of any size used for various purposes.
Line of Position – A line on a chart along any part of which a vessel might be.
Liner – A vessel operating in common carrier service on a regular route and schedule.
List – Permanent or semi-permanent inclination of a ship to one side or the other as distinct from heel.
Longitude – Measure of angular distance in degrees, minutes and seconds east or west of the Prim Meridian at Greenwich.
Longitudinal – A general term meaning fore and aft.
Longshoreman – A man who works aboard ship at loading or discharging vessels or on the terminals at handling, loading or unloading freight received from or delivered to vessels. Because of the divisions of the operations, longshore labor is divided into two parts, those who work on the ship or stevedores and shore gangs or dock workers.
Look Alive – Meaning be alert, move quickly.
Loom – The glow visible in the sky before a light is actually seen.
Loran – Long Range Electronic Navigation. A system of electronic navigation in which the time difference in the reception of pulse signals originated simultaneously at a master and slave station is used to locate a vessel on a charted hyperbolic curve that is the  focus of all possible positions which would observe the identical time difference. The intersections of two such lines results in a fix.
Lubber – Someone unused to being aboard ship.
Lubber’s Line – The index mark on a compass from which the course is read and the vessel is steered.
Lubberly – Unseamanlike.
Luff – To put the helm so as to bring the vessel up nearer the wind. To move a load toward or away from the axis of a rotating crane.
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Maiden Voyage – First voyage made by a vessel after she has undergone all her trials and has been put into regular service.
Manhole – A round or oval hole cut in floors for the purpose of providing access.
Maneuvering Board – A plotting sheet laid out in polar coordinates.
Marline – A tarred hemp cordage made of two threads, used in worming, serving and small seizing in the finer class of work.
Marlinespike – A pointed iron or steel tool used to separate the strands in splicing rope, and as a lever in marling or putting on seizings.
Marry – To join ropes together by worming over both.
Mast – A long pole of steel or wood which is erected vertically on the center line of a ship.
Master – the commander of a vessel.
Mayday – International distress signal.
Mean High Water – The average height of high tidal water measured over a period of time.
Mean Low Water – The average height of low tidal water measured over a period of time.
Mean Sea Level – The level half the distance between mean high and mean low tidal water.
Mediterranean Moor – Mooring a ship with stern to seawall and bow kept from swining by anchor(s) placed ahead while maneuvering.
Meet Her – An order to the steersman to apply opposite rudder to check or stop ship from swinging.
Meridians – Great circles of the earth that pass through the poles. Used for measuring longitude.
Messenger – Light line used to carry across a larger line or hawser.
Mile – A statute mile is 5280 feet. A nautical mile is slightly more than 6076 feet.
Mind Your Rudder – A caution to the steersman to steer a more precise course or to be alert to some special circumstances such as meeting a current.
Mole – A large, solid-filled nearshore structure of earth, masonry or large stone; used as a breakwater or pier.
Monkey’s Fist – A heavy knot placed in the end of a heaving line to give it weight which helps get accuracy when it is heaved.
Moor – To secure a ship alongside a pier.
Mooring Bitts – A term applied to the bitts to which the mooring lines are attached.
Mooring Line – Line used to secure a ship to a pier.
Mooring Ring – A round or oval casting inserted in to the bulwark olating through which mooring lines or hawsers are passed.
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Nadir – that point on the celestial sphere vertically below the observer.
Navigation – The art of conducting a ship from port to port.
Navigation Lights – Lights displayed by a vessel that indicate course, position and occupation.
Neap Tide – The decreased tidal action occurring at first and last quarter moons.
Net Tonnage – the capacity of a vessel which is determined by subtracting engine room, crew quarters, stores and navigation space from the total hull interior of a vessel.
Nip – To stop a rope by attaching another to it with several turns of yarn alternately around each and the ends made fast.
Nipple – Short connector.
Notice to Mariners – A publication giving latest changes to navigational charts and other aid.
Not Under Command – Said of a ship when she is disabled and uncontrollable through some exceptional circumstance and is unable to maneuver as required by the Rules of the Road.
Null – The point of least signal.
Nun – A variety of cylindrical buoy tapered at the top and typically painted red.
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Occluded Front – An intermingled cold front and warm front.
Occulting – A system of flashing in which the ons are longer than the offs.
Old Man – Slang for the commanding officer of any activity.
On The Bow – Said of an object somewhere ahead on one bow or the other.
On The Double – Quickly.
On The Quarter – Said of an object somewhere astern but not directly astern.
On The Wind – Close hauled.
Outward Bound – Said of a vessel when putting to sea from her home port.
Overhaul – To repair or put in proper condition for operation.
Overtaking Vessel – One that overhauls another.
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Pad Eye – A fitting having an eye integral with a plate or base in order to distribute the strain over a greater area and to provide ample means of securing.
Painter – A line in the bow of a boat for making fast.
Parallax – The difference between the true and apparent direction of sighting.
Parallel of Latitude – A circle on the surface of the earth parallel to the plane of the equator and connecting all points of equal latitude.
Parallel Ruler - A double, connected ruler used on charts to transfer courses and bearings to and from the compass rose. See protractor, drafting machine, compass rose.
Part – To break.
Passage – One leg of a voyage.
Passageway – Corridor or hall aboard ship.
Pass a Line – Throw or project a line.
Pay Out – To slack off or ease out a line.
Pendant – A single part of line or wire whose purpose is to provide a means for connecting or disconnecting.
Pier – A structure extending out into the water and providing a means for vessels to moor alongside.
Pillar – A vertical member or column giving support to a deck.
Pilot House – The compartment in the bridge structure that contains the ship controls and from which the ship is normally controlled.
Pilot Ladder – A ladder, one end of which is secured on deck, the other end being thrown over the ship’s side to permit the pilot to climb on board.
Pintle – A pin fastened to a rudder that fits into a gudgeon.
Pitch – A term applied to the distance a propeller will advance during one revolution.
Pitchpole – To pitch down end over end.
Planing Hull – A hull designed so that forward speed creates water lift resulting in reduced friction and increased speed.
Planing Speed – The minimum speed required by a planning hull to rise on a plane.
Plimsoil Mark – A mark stenciled in and painted on the side of a vessel designating the depth to which the ship may be loaded.
Plumb – Vertical.
Plumb Bob – A top-shaped weight suspended from the end of a cord to test the plumb or perpendicularity of an object. Also used in connection with a steel tape in sounding ships’ tanks.
Porpoising – Moving forward with short leaps from the water.
Porthole – Round opening on the side of a ship.
Position – The location of an object relative to a reference point or in accordance with recognized coordinates as longitude and latitude.
Preventer – Any line used for additional safety or security or to keep something from falling or running free.
Privileged Vessel – Ship having right of way under Rules of the Road and required to hold course and speed.
Propeller – A rotating device with two or more blades that acts to propel a vessel.
Propeller Shaft – The short aftermost section of the main shafting to which the propeller is attached.
Prow – A term for the bow of a ship.
Purchase – An application of mechanical power.
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Quartering – Running at an angle to the sea.
Quarters – Living spaces for passengers or personnel.
Quay – A loading and discharging place parallel to the shore.
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Rabbet – A groove in a structural member into which another fits and is fastened.
Radar – Radio Detection and Ranging; an instrument for determining, by radio echoes, the presence of objects and their range, bearing and elevation.
Rail – Upper edge of the bulwarks.
Raise a Purchase – To arrange tackle in such a way that sufficient mechanical advantage is gained to move a particular object.
Rake – The fore and aft inclination from the vertical.
Range – The distance an object is from an observer.
Rat Guard – A circular piece of metal placed on hawsers and lines to prevent rats from going on board the vessel while at a dock or wharf.
Ratlines – Short lengths of ratline stuff secured to the shrouds parallel to the waterline and serving as ladder rungs for the crew to ascend or descend.
Reach –A point of sailing with the wind near the beam.
Ready About – An order to the crew to be at their stations for putting a sailing ship about.
Reciprocal – A direction precisely opposite another.
Reduction Gear – Gear used to reduce the economical high speed of a ship’s turbine to the necessarily slower shaft and propeller speed.
Reef – To reduce sails.
Reeve – To pass or thread a rope through a block or hole.
Relative Bearing – A direction in relation to the centerline expressed in degrees.
Rhumb Line - A line on the earth’s surface making the same angle with all meridians. It is a straight line on a Mercator projection chart and is the standard way of laying down a ship’s course.
Rigging – a term used collectively for all the ropes and chains employed to support and work the masts, yard, booms and sails of a vessel.
Right the Helm – To bring the helm amidships.
Rime – The rung of a ladder.
Roaring Forties – Area between 40 degrees and 50 degrees south latitude in which the stormy westerlies are encountered. This area develops very high seas because of an absence of land masses and consequent unlimited fetch.
Roger – Used in voice radio, meaning I have received your transmission.
Roll – Transverse motion of a ship about its longitudinal axis.
Roller – A long usually nonbreaking wave generated by distant winds and a source of big surf, which is a hazard to boats and a delight to surfers.
Roll-on/Roll-off (RO/RO) – Method in which the cargo is loaded into vehicles that drive on board ship and remain, to drive off at destination.
Rough Log – Original handwritten and legal version of the ship’s log. Incorrect entries may be lined out., but not erased.
Rudder – A device used in steering or maneuvering a vessel.
Rudder Stop – Lug on stern frame or a stout bracket on deck to limit the swing of the rudder.
Running Fix – Geographical position determined by two lines of position obtained by observations at different times. First line is advanced by dead reckoning.
Running Light – Any one of the lights required to be displayed by a vessel while underway.
Running Rigging – The adjustable lines used for the control of spars and sails.
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Sail Area – The vertical hull Surface of a ship on which the wind exerts force.
Sailing Instructions – Orders pertaining to a particular voyage.
Salty – Nautical; seagoing; sometimes means raffish, cocky, unconventional, earthy.
Salvage – Cast off, discarded material. To save or rescue material that has been discarded, wrecked, sunk or damaged. The act of salvaging a ship.
Samson Post – A single bitt in the bow of a small boat.
Scale – the relation between distance on a chart and the actual distance.
Scantling – A piece of timber used in ship construction.
Scarf – A joint made between two members by tapering and overlapping them.
Scope – Number of fathoms of chain out to anchor or mooring buoy.
Screw – The propeller of a ship. A wheel.
Scull – to propel a boat with one oar worked against.
Scupper pipe – A pipe conducting the water from a deck scupper to a position where it is discharged overboard.
Scuppers – Drains from decks to carry off accumulation of rainwater, condensation or water.
Scuttle – The act of deliberately sinking a vessel. Small opening in a hatch cover that allows access without undogging the hatch.
Scuttlebutt – Slang for rumor or gossip.
Sea Anchor – A conical-shaped canvas bag required to be carried in each lifeboat. When placed overboard it serves a double purpose, i.e., it keeps the boat head on to the sea and also spreads a vegetable or animal oil which is supplied by a conical-shaped container  placed inside the bag. Sometimes called an oil spreader.
Sea Buoy – The first buoy encountered coming from the sea.
Seacock – Valve in the ship’s hull connected to the sea.
Sea Dog – An old sailor.
Seagoing – Adapted or fit for going to sea.
Sea Legs – Adaptation to the motion of a vessel in a seaway.
Seam – A term applied to an edge joint.
Seamanship – The nautical art.
Seawall – A barrier along the shore line to prevent encroachment of the sea by direct wave action.
Seaway – A moderate to rough sea.
Seaworthy – Capable of putting to sea and meeting any usual sea condition.
Secure – To make fast in a permanent sense.
Seize – To bind with a small rope.
Set – To hoist and trim sails.
Set the Course – To give the helmsman the desired course to be steered.
Set the Watch – To establish the regular routine of watches on a ship or station.
Settle – To sink deeper into the water.  
Sextant – Navigational device used to measure the angular distance between two objects, usually between the earth’s horizon and a celestial body.
Shackle – U-shaped metal fitting, closed at the open end with a pin, used to connect wire and chain.
Shackle Bolt – A pin or bolt that passes through both eyes of a shackle and completes the link.
Shaft Alley – The space in a ship through which the propeller shafts extend from the engine room to the propeller.
Shank – The central shaft of an anchor to which the flukes are attached.
Shear Pin – a device used to fasten a propeller to its shaft and designed to break upon contact with a solid object and thereby preventing further damage.
Sheer – The curve of a deck as seen from the side.
Sheer Off – To steer away from.
Sheer Strake – The topmost plank in a hull.
Sheet – a line used to control the lateral movement of a sail.
Shelf – A longitudinal member supporting the deck beams.
Shellback – One who has crossed the equator and was accepted by Davy Jones.
Shift – The changing of position of a vessel from one berth to another at the same wharf or between wharves within port limits.
Shiphandling – The art and skill of directing the movements of a ship in formation, tactics and maneuvers in restricted waters or in docking and mooring.
Shipmate – Person with whom one is serving or has served, particularly at sea.
Shipshape – In good order and condition.
Ship’s Bell – A bell and clapper of the usual shape used aboard ship as a means of denoting the time at regular intervals by day and night.
Shipwright – An individual skilled in building and repairing ships.
Shiver – To shake the wind out of a sail by bracing it so that the wind strikes upon the leech.
Shoal – An area of shallow water.
Shoe – A strip fastened to the bottom of a keel.
Shore – A brace or prop used for support while building a ship or for use in damage control.
Short Handed – Said of a vessel which does not have her full complement of crew.
Shove Off – Slang for depart.
Side Light – One of the colored lights required to be displayed by a vessel underway.
Sidereal – Pertaining to the stars.
Single Up – A command given before unmooring a ship from a wharf or pier.
Skeg – Continuation of the keel aft under the propeller and supporting the rudder post.
Skids – A skeletal framework used to hold structural assemblies above ground while ashore.
Slack – The opposite of taut. Allow a rope or chain to run or feed out.
Slack Water – A period of little or no water movement between flood and ebb tidal currants.
Slew – To turn something on its own axis. To swing a boom around.
Slick – A smooth area on the surface of the sea, caused by oil, variable winds, the sliding stern of a ship turning, etc.
Slip – Space between piers.
Slop Chest – A room on a vessel where ready-made clothing, tobacco, cigarettes, toothpaste, tooth brushes, safety razor blades, etc. are kept for sale to members of the vessel’s crew during a voyage.
Sludge – Sediment in fuel oil tanks.
Small Stuff – Any yarn, cord or line less than one inch in circumference.
Smart – Neat; shipshape; efficient; military; quick.
Soft Laid – Rope in which the strands are loosely laid to allow for greater pliability.
Sole – The cabin or cockpit floor.
Sounding – A measure of the depth of the water.
Sounding Pipe – A pipe leading to the bottom of a tank used to guide the vehicle for sounding.
Splash Boards – Boards rigged on stern of small craft to keep water out of cockpit.
Splice – To join two lines or two parts of a line by unlaying them and intertwining their strands.
Squall – A sudden and violent windstorm often accompanied by rain.
Square Away – To straighten, make shipshape or to get settled in a new job or home.
Square Rigger – A sailing ship, the majority of whose sails are square sails.
Square Sail – A sail cut into an approximate square or rectangular shape and mounted on yards which extend equally on both sides of a mast.
Stability – The tendency which a vessel has to return to the upright when inclined away from that position.
Stadimeter – An instrument for measuring the distance to an object of known height.
Stage – Platform hung over the side of a vessel or in a hold to provide for sailors to work from.
Stanchions – Short columns or supports for decks, hand rails, etc. Stanchions are made of pipe, steel shapes or rods according to the location and purpose they serve.
Stand – Brief period of no change in water level at high or low tide.
Stand By – To wait.
Starboard – Directional term for right.
Start – To ease an anchor off the ground.
Station Bill – List of all members of the crew with an assignment of posts for all boat, emergency and fire drills.
Staunch – Said of a vessel that is well built, sturdy and free of leaks.
Stave Off – To thrust a boat or floating object away from a jetty or a vessel with a spar or boat hook.
Steam Capstan – A vertical drum or barrel operated by a steam engine and used for handling heavy anchor chains, heavy hawsers, etc.
Steerage – The least desirable portions of a vessel as to accommodations for passengers and occupied by those paying the very lowest fare.
Steerageway – The lowest speed at which a ship can be steered.
Stern – The bow frame forming the apex of the intersection of the forward sides of a ship.
Sternpost – The main vertical post in a stern frame upon which the rudder is hung.
Sternway – A reverse motion through the water.
Stock – The crossbar in the shank of an anchor.
Stop – To plug a leak in a seam or a joint.
Stopper – A line or chain used for stopping off a rope or chain.
Stopwater – Canvas or other material fitted between two metal parts to form a watertight joint.
Stores – Supplies.
Stove In – Broken by external force.
Stow – To put away. To store cargo in the hold.
Stowage – The proper distribution and securing of cargo in a vessel so as to avoid damage to either cargo or vessel by the shifting of cargo or by the undesirable conditions of trim and stability resulting from such a shift.
Stowaway – Person who hides on a ship in order to obtain free passage.
Strain – The measure of the alternation of form which a solid body undergoes when under the influence of a given stress.
Strake – A term applied to a continuous row or range of plates. The strakes of shell plating are usually lettered, starting with A at the bottom row.
Strike – To lower.
Strut – A heavy arm or brace.
Stuffing Box – A device which fits around the propeller shaft allowing it to rotate without the seepage of water.
Superstructure – All structure above the main deck of a ship.
Surveyor – A professional who examines boat and ship.
Swab – Mop.
Swallow – A term applied to the oval or round opening in a chock or mooring ring.
Swamp – To fill with water coming over the deck and gunwales.
Swell – An undulating breakerless motion on the surface of the sea.
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Tack – The forward bottom corner of a sail or either lower corner of a sail or either lower corner of a square sail. To come about head to wind.
Tack Rag – A slightly sticky cloth used to pick up dust and dirt from brightwork before varnishing.
Tacking – The sailing maneuver in which the direction of the boat is changed so that the wind approaches from the other side of the vessel.
Tackle – Any combination of ropes and blocks that multiplies power.
Taffrail – A term applied to the stern rail of a vessel.
Take a Strain – To apply tension on a line, wire or chain.
Take a Turn – To pass a line around a cleat or bitts.
Taut – Under tension.
Telegraph – An apparatus used for transmitting orders from one section of the vessel to another.
Tell Tale – An indicator which displays the direction of the wind which is mounted on the rigging, mast or sail.
Tend (to) – To Take care (of).
Tender – A small boat which carries people to and from a larger vessel and used to assist in the maintenance and repair of the larger vessel.
Tender Ship – A vessel that heels over easily when underway; often due to storing cargo too high in the ship.
Thimble – An iron or steel ring with a concave exterior so as to allow rope or wire to fit snuggly around.
Three Sheets to the Wind – Intoxicated.
Tiller – A handle which directs the steering of the rudder.
Toe Rail – The low bulwark on a small decked boat.
Top Off – To fill up.
Topside – That portion of the side of the hull which is above the designed water line.
Tow – To pull along through the water.
Tow Line – Hawser passed from one vessel to another for purpose of towing.
Towing Bitts – A term applied to the bitts fitted on the deck of a vessel for the purpose of belaying or fastening the towing hawsers.
Towing Winch – Special winch, used by large tugs in towing, which compensates for variation in the tension on the towline.
Track – The actual path of a vessel over the ground.
Transom – The transverse part of the stern.
Transverse – At right angles to the centerline of a vessel.
Tread – The length of a vessel’s keel.
Trick – Period of duty at the wheel.
Trick Wheel – Steering wheel in the steering engine room or emergency steering station of a ship.
Trim – The difference between the draft forward and the draft aft.
Trip – To raise an anchor clear of the bottom. The situation encountered by a tug when the tow exerts lateral force on it.
Trip Line – A line fast to the crown of an anchor used to assist in recovery.
Trough – The depression in the water between a set of waves.
Truck – The very top of the mast.
True Bearing – Direction of an object relative to true instead of magnetic north.
True Heading – Horizontal direction in which a ship is heading, relative to true north.
True Wind – The actual direction and force of the wind.
Tumblehome – The inward curving of the topsides above the waterline.
Tune – To adjust the rigging and sails for maximum efficiency.
Turnbuckle – Metal appliance consisting of a threaded link with a pair of opposite-threaded screws with eyes, capable of being set taut or slacked and used for setting up standing rigging or other gear.
Turn Turtle – To capsize or to founder.  
Typhoon – A hurricane in the Eastern seas.
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Underway – Said of a vessel when she is not made fast to the ground in any manner.
Unship – To remove something from the place in which it was secured.
Up Behind – An order to cease hauling and to slack a line quickly.
Upwind – To the windward of.
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Vane – A fly made of bunting and carried at the truck, which being free to rotate on a spindle, indicates the direction of the wind.
Vang- Line used to steady or support a boom or spat.
Variation – Magnetic compass error caused by the difference between the geographic and magnetic poles.
Vector – A line drawn to represent magnitude and direction.
Veering – Changing direction, used in referring to the wind and also to the course of a vessel.
Vessel – The word vessel includes every description of water craft or other contrivance used or capable of being used as a means of transportation in water, but does not include aircraft.
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Waist – The amidships section of the main deck.
Wake – The disturbed water left behind a moving vessel.
Warp – A light hawser or tow rope; to move a vessel along by means of lines or warps secured to some fixed object.
Warping – A term applied to the operation of moving a vessel from one place to another about a dock or harbor by means of hawsers.
Wash – The broken water left behind a vessel as it passes through the water.
Watch – Duty period, normally four hours long.
Watch Below – General term for time off.
Water Taxi – Shore boat, available for hire like a taxi.
Waterline – The line of the water’s edge when the vessel is afloat.
Watertight Bulkhead – a partition of planking or plating reinforced where necessary with stiffening bars and capable of preventing the flow of water under pressure from one compartment to another.
Waterway – A narrow gutter along the edge of the deck for drainage.
Way – Movement of a vessel through the water.
Weather Deck – Any uncovered deck which is not protected from the weather or the sea.
Weather Eye – To keep a weather eye is to be on the alert.
Weather Helm – The tendency of a vessel to turn slightly to windward.
Weather Side – The side of a vessel upon which the wind blows.
Weather Working Days – Days during which the weather enables cargo to be unloaded without hindrance or delay.
Weep – To leak very slowly.
Weigh – Nautical term for lifting.
Weigh Anchor – Hoist the anchor clear of the bottom.
Well Deck – Part of the weather deck having some sort of superstructure both forward and aft of it.
Well Found – said of a ship that is fully equipped.
Wheel – Another term for propeller or screw. The instrument attached to the rudder by which a vessel is steered.
Whelps – Projections on the periphery of the wildcat drum that fit the anchor chain and pull it by a sort of gear-tooth action.
Wherry – Light, handy pulling boat with a transom stern.
Whip – The term whip is loosely applied to any tackle used for hoisting light weights and serves to designate the use to which a tackle is put rather than the method of reeving the tackle.
Wide Berth (to) – To keep well clear of another boat.
Wildcat – A special type of windlass drum which is formed to fit the links of an anchor chain. The rotating wildcat causes the chain to slack off when the anchor is lowered and hauled in when raising it.
Williamson Turn – Maneuver used to recover a man lost overboard by placing the rudder over toward man at 70 degrees from original heading to return to reciprocal of original heading thereby returning to lost crewman.
Winch – An item of small machinery containing a revolving barrel that gives a mechanical advantage in hoisting. It is used for raising and lowering ropes, mooring a vessel, hoisting cargo, etc.
Wind Dodger – A canvas wind shield used on a vessel’s bridge.
Working Strain – The maximum load that can be applied to a working rope.
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Yard – A spar from which a square sail is hung.
Yardarm – The crosspiece near the top of a mast.
Yaw – The act of sheering suddenly and unintentionally from a vessel’s course.
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Zenith – That point of the celestial sphere vertically overhead.
Zerk Fitting – Small plug to which a grease gun can be applied to force lubricating grease into important parts of machinery.
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