Sailing Terms Glossary
Educate and learn about sailing using our glossary of sailing and maritime terminology. Whether you sail a dinghy, a pram, or a yacht; this dictionary lists the commonly used vocabulary of sailors on recreational, cruising and racing sailboats. General nautical terms that lend themselves to both power boats and sailboats are included. Additionally, in this glossary, you may find a few funny and fun nautical terms and phrases, and a bit of slang too.
Click on a letter below to jump to the terms starting with that letter.
Abandon Ship: A command to leave a vessel due to imminent danger.
Abeam: A relative direction that is always at a right angle to the vessels direction of travel.
Aboard: Literally meaning to be “on board” a vessel.
Adrift: Afloat and detached from the shore or seabed, but not making way. Drifting with the wind or current.
Aft: Any portion of a vessel behind the centerline.
Aground: When a vessel is resting on the seafloor
Aloft: Refers to anything that might be above deck in the rigging or mast.
Anchor: A metal hook-like device designed to attach to the seafloor in order to slow or stop a ship.
Anchorage: A designated area for boats to anchor in.
Anchor Light: A 360° white light displayed by a vessel at anchor.
or chain specifically designed to hold a ship to its anchor.
The velocity and direction of the wind in relation to an observer in motion.
Ashore: To be on land
Astern: Towards the back of the vessel.
A device that uses the suction created from forward momentum to drain water from the inside of a boat.
A wire or rope used to support the mast from an attachment point at the stern of a vessel.
A device used to remove water from the inside of a boat.
Bar: Mass of sand or mud formed by the movement of water which creates an area of shallow water.
Barge: A flat bottomed boat designed to carry heavy cargo, mainly through inland waterways.
A thin strip of material used to create rigidity and shape in sails or canvas.
Beam: A measurement of the widest point of a vessel.
Beam reach: Sailing at an angle approximately 90° to the apparent wind, such that the wind is crossing the vessel’s beam.
The direction of a line between two waypoints.
Beating: Sailing in a zigzag course so as to make progress upwind.
A stepped scale defining wind strength
, and its resulting effects, devised by Admiral Sir Francis Beaufort in 1808.
Becalm: A complete lack of wind, rendering sails useless.
Below: Any area of a boat below deck level. Downstairs.
Bend: Any type of knot used to join two lines together.
Bermuda rig: A sailing vessel designed with one tall mast and triangular sails.
Berth: (1) Sleeping accommodation on a boat. (2) A specified location for a boat when not at sea.
Bight: Any knot tied in the middle of a line.
A compartment at the bottom of a vessel designed to collect water to be pumped out
Bimini: A sunshade supported by a metal frame.
Bite: A rudder
“bites” when water begins to flow past it, creating resistance and positive feel at the helm of a vessel.
Bitter End: The end section of a rope.
Blade: Slang term for a centerboard or rudder.
A pole with a hook on one end, designed to grab anything that might be outside the vessel. (generally dock lines, moorings, etc.)
Bobstay: A wire or rope designed to hold a bowsprit downwards; works in conjunction with the forestay.
Boom: A spar
designed to hold a sail outwards. Aptly named for the noise it’s known to make against the side of a sailors head.
A purchase system
with the purpose of holding a boom down (nearer to head level). Also has the side effect of controlling the leach tension of a sail.
A canvas chair attached to a halyard, designed to hoist a person aloft.
Bow: (1) The front most portion of a vessel. (2) Exactly one half of a dog’s bark.
A small, but sometimes important device; designed to keep a sailboat crew from keelhauling their own sheet lines.
A line employed at the bow, to hold a vessel to a dock or other structure.
Bow sprit: A spar protruding from the bow used to attach various rigging.
Bowline: A very practical and strong knot.
A length of wire or rope joined together at a midpoint; designed to distribute load in two or more directions.
Brightwork: Any varnished wood or polished metal found on a boat.
A first place victory
in a sailing race.
Bulkhead: A load bearing wall inside of a vessel. May or may not be watertight, depending on how old your vessel is.
An anchored, floating object, which defines a given position. Used as an aid for navigation.
Burgee: A small triangular flag used to indicate membership to a particular yacht club.
Cabin: Refers to the interior living space of a vessel.
Capsize: When a boat overturns in the water.
Captain: A person whom is assigned command of a vessel.
Catamaran: A sailing vessel with two hulls.
Catboat: A sailing vessel with one mast close to the bow, and a “gaff”‘ to support the sail.
Cat’s paws: Area of small ripples on the surface of the water, created by very light wind on an otherwise becalmed sea surface.
Center of effort: The geometric center of force created by the wind on the sails. Subject to change based on sail shape and wind direction.
Centerline: An imaginary line drawn lengthwise through the center of a vessel.
A board which pivots downward into the water in order to stop sideways slippage, and generate forward momentum by working in conjunction with the sails to create lift.
Any wear to running rigging or sails, created by unwanted friction.
A block designed to be mounted to the side of a surface.
Chine: A line formed lengthwise on the hull of a boat where two different angles meet.
Class: A group or classification of similar sailing vessels; see “one design”.
A broad classification of devices used to secure a control line, sheet, or halyard on a boat.
Clew: The aft most corner of a triangular sail.
Close-hauled: Sailing as close to the true wind direction as possible.
A set of jaws, similar to a cleat
, designed to hold a rope fast under high loads.
Coaming: A raised lip or edge to prevent water intrusion near a hatch or porthole.
Coastal: Of or referring to the coast.
Cockpit: The seating area of a small vessel toward which most of the controls are run.
Come about: To change direction through the wind.
Come to: To stop a vessel by turning into the wind.
Commodore: The chief officer of a yacht club. Commonly deals with more political issues than all of the combined nations on this planet.
Companionway: A raised hatch, with a ladder leading below deck.
A magnetic instrument
which shows direction of travel in relation to Earth’s magnetic poles.
Constant bearing: When the angle of an approaching vessel remains the same over time, Indicating a collision course.
Course: (1)The route to be taken around a buoy race. (2)The current direction of travel.
Crew: Any persons aboard a vessel whom are neither the skipper, nor passengers.
A line which provides downward force on the luff of a sail, in order to fine tune sail shape.
A board pushed directly downward through the hull into the water: works in conjunction with the sails to provide forward momentum by creating lift, and minimizing sideways slippage.
Davit: A spar used to hoist a smaller dinghy, or tender, aboard a larger vessel.
Davy Jones’ Locker: An idiom referring to the bottom of the sea. Used as a euphemism for any person, shipwreck, or object lost to the sea.
Dead in the water: Used as a reference to a loss of power when previously underway.
Death roll: Slang term for a particularly epic capsize or wipeout. Especially when going downwind at speed.
Deck: The topside of the hull on which the crew works.
Dinghy: (1) A small sailing vessel, or (2) a small boat carried by a larger ship to act as a tender.
Displacement: The weight of a ship, as determined by the relationship between the mass and volume of the same weight in water.
Dock: A structure built over the water to which ships are secured.
Dodger: A hood over a hatch to protect from wind and spray.
Doldrums: A becalmed area in the Atlantic Ocean notorious for hurricane formation. Slang term sometimes referring to a similar becalmed area on a race course.
Downwind: Point of sail 180° from the true wind direction.
Any piece of line or rigging designed to apply downward force to a sail, spar, or blade.
Draft: (1) The depth of a vessel’s lowest point from the waterline.
Drifter: A sailing race in which there is no wind. Hence all boats are merely drifting.
East: One of the four cardinal directions.
Ebb: Tidal movement out to sea.
Eddy: A current of water moving against the main flow. Often causes small whirlpools.
Generally refers to the amount of time that has passed since the start of a sailing race.
Electrolysis: A small amount of electric current that passes between dissimilar materials. Causes corrosion on the spars and rigging of many sailing vessels where dissimilar materials are in constant contact.
Emergency tiller: A backup steering device used in the event of primary steering failure.
End for end: The act of reversing and re-splicing a halyard, sheet, or other running rigging in order to repair, or extend its useful lifespan.
Ensign: Nautical flag used to display a vessel’s country of origin.
A distress beacon
, triggered by a vessel in need of rescue. (2) Known in some circles as an “emergency pre-race beer”.
Even keel: Said when a vessel is sitting level to the surface of the water.
A fixed loop, or attachment point at the end of a line.
Fair: (1) Referring to a smooth curvature of a vessels hull. (2) To make a surface flush.
A device used to keep a line running in the correct direction.
Fall off: To change direction so as to head more downwind.
Fathom: A unit of length used to measure depth, equal to six feet.
Feathering: Sailing a fine directional line between two points of sail, usually close hauled and irons.
Fend off: A command given to the crew to manually prevent the boat with colliding with something, usually at low speed.
A bumper designed to act as a cushion between a boat and the dock.
Fetch: The length of an area over water where waves are being generated by the wind.
A splicing tool designed to facilitate the making of various splices in rope or wire.
Fixed propeller: A permanently mounted propeller protruding from the hull of a vessel.
Flemish eye: A type of reeving eye in line, designed to facilitate in the installation of a halyard through a mast.
Foil: Can refer to either (1) The hydrodynamic “wing shape” of a sailing vessel’s keel and rudder, or (2) The thin, pliable, pieces of metal overtop of the forestay onto which a jib or headsail is attached.
Folding propeller: A type of propeller with blades that fold inward in order to reduce drag on a sailboat.
Following sea: Wave action that is traveling in the same direction as a ship.
Foot: The lowest edge of a sail.
Fore: Towards the bow.
Foresail: The forward most sail on a vessel.
A line or cable attached from the bow to the mast, in order to provide structural support to the mast.
Any entangled lines, rigging, or equipment. (2) An infraction of the rules
in a sailing race.
Founder: Another word for sinking, or “to sink”.
Frame: Structural cross member of a ship’s hull.
Freeboard: The length hull exposed above the waterline.
Fully battened: Refers to a sail that has thin strips of batten across its entire width to provide better sail shape.
Gaff: A spar that holds the upper edge of a sail.
Gaff rigged: Any such vessel that is rigged using a gaff.
Galley: The kitchen
Gangplank: A mobile bridge to facilitate loading/unloading of persons and cargo onto a ship.
Gennaker: A type of lightweight crossover sail, designed to sail intermediate angles when neither a spinnaker, nor a Genoa would be suitable.
Genoa: A jib with a large overlap past the mast.
Gibe: See “gybe”
Gin-pole: A spar designed to facilitate raising and lowering the mast.
The attachment point between the boom and mast. Allows the boom to move freely in any direction.
Granny Knot: An incorrectly tied knot.
One half of a fitting which attaches a ship’s rudder to her hull.
Gunwale: The upper edge of the hull, generally where the sides meet the deck.
Gybe (or jibe): To change direction through the wind.
Hail: A greeting designed to catch the attention of someone, often in reference to radio communication.
Half Hitch: A simple knot made around an object.
: The line
on a sailboat used to raise, adjust, and lower sails.
A mobile marine communications radio.
Hank: A small fastener which attaches a sail to the forestay.
Harbor: A sheltered area of water where vessels may take refuge or dock.
Hard-chined: A vessel designed with a sudden change of angle lengthwise in the hull, usually placed near the waterline.
Hard Over: A warning issued by the skipper, telling the crew that the tiller has been pushed hard over to one side Indicating that a sudden directional change is imminent.
A covered opening in a ship’s deck.
Hauling out: To crane a boat out of the water and place her “on the hard”.
Head: The toilet or lavatory of a ship.
Header: A wind shift towards a vessel’s direction of travel, causing a turn to a more downwind course to correct for the shift.
Heading: A direction given in degrees on a compass or map.
Any sail set forward of the mast.
Head to wind: Having the bow of a vessel pointed directly into the wind.
Headway: Progress in a forward direction.
Head wind: A wind direction that is directly opposed to the direction of travel.
Heave to: A heavy weather technique designed to stop a vessel, but keep her pointed in the correct direction.
The sideways incline of a sailing vessel due to the force of the wind.
Holding tank: The tank on a ship where sewage is held until proper disposal is possible.
Hull: The watertight shell and framework of a ship.
Hydrofoil: A wing like structure, or foil, capable of lifting the hull of a vessel out of the water at speed.
Icing: A serious weather condition where high winds combine with freezing temperatures, creating rapid ice accumulation on contact with any part of a ship.
Inboard: Can refer to anything situated within a ship.
Instrument for measuring angle of slope, or heel on a sailing vessel.
A specific set of maritime traffic laws applying to inland waterways.
Inlet: (1) A geographic feature that connects two bodies of water. (2) A fitting in a ship’s hull to allow seawater to enter or exit.
Inshore: Geographic area of water within a certain distance of land.
Intracoastal Waterways: A 3,000 mile stretch of navigable waterways, located in protected inland waters along the Atlantic and Gulf coasts.
Irons: When the bow of a boat is stuck into the wind, resulting in stalled sails and the inability to maneuver.
Isobars: Lines on a map connecting points of equal atmospheric pressure.
Jenny: Slang term for a genoa sail.
Jetty: A man made wall of rock or rubble, intended to act as a barrier from the sea.
Jibe: To change direction through the wind.
Jibe-ho: A warning issued before jibing a sailboat.
Jury rig: A makeshift repair. Often turns into a permanent repair on some vessels.
Keel: Fin like appendage protruding from the bottom of a sailing vessel that provides hydrodynamic stability and lift.
Keelhauling: A form of punishment at sea by which sailors were tied to a rope and dragged underneath the ship.
Ketch: A sailing vessel with two masts.
Slang term for a type of rigid boom vang
that can provide support to the boom when not underway. Eliminates the need for a boom topping lift.
Knock: Another term for header.
Knockdown: When a sailboat is suddenly pushed onto its side, either by an abrupt wind gust or rouge wave.
(1)A unit of speed equal to one nautical mile per hour. (2) A method of securing rope
Land lubber: A sailor’s term for anyone unfamiliar with the sea.
A small one design sailboat designed by Bruce Kirby.
A triangular sail set on a long spar mounted at an angle to the mast.
Lay: The twist or braid of a rope or wire.
Layline: When zigzagging upwind, a layline is the last leg or bearing from which a vessel can reach her destination on a close-hauled course.
Lazaret: A storage locker towards the aft end of a boat.
Lazy Jacks: An arrangement of lines designed to cradle and stow a sail along the boom when not in use.
A small diameter line used to pull a larger line through a mast, spar, or other rigging.
League: A unit of length equal to three nautical miles.
Lee shore: Area of land downwind of a ship.
Leech: Aft most edge of a sail.
Leeward: Relative direction downwind from a point of reference.
Leeway: Amount that a ship slides to leeward
Leg: One segment of a sailing race or journey.
Length overall: The length of a vessel from one end to the other.
Lifeboat: A small craft carried on a ship for use in an emergency.
Lift: A force created by the flow of a fluid past an object.
Correct nautical terminology for a rope.
Luff: Forward most section of a sail.
Magnetic north: Direction that points towards the Earth’s magnetic pole.
Mainmast: Refers to the largest mast on a vessel with more than one mast.
Making Trees: Slang term for progress made against competitors in a sailing race.
An emergency signal
indicating that someone has fallen into the sea.
Maritime: Anything relating to the sea.
Rope working tool used for splicing and untying knots.
Mast: A spar, or pole, which supports the rigging and sails of a vessel.
A platform or fixture at the top of a mast from which rigging, blocks, tackle, and lighting may be attached.
Midships: Referring to the middle section of a vessel.
Mizzenmast: A secondary mast placed behind the main mast.
Monkey’s fist: A specialized knot used to facilitate in the throwing of a line.
Mooring: Any permanent structure, or anchor, to which a vessel may be secured.
As in, “mousing a shackle”; Method of securing a shackle pin or other rigging with seizing wire
Narrows: The narrowest section of a navigable waterway.
Nautical mile: A distance corresponding to one minute of arc of latitude.
The “rules of the road” that provide the means for organized maritime traffic.
Nun: A cone shaped navigational buoy.
Offshore: The geographical area of water away from the coast.
Old salt: Slang term for an experienced sailor.
A system of racing sailboats in which all competing vessels are of equal design, construction, sail plan, rigging, etc.
Outboard: (1) Referring to anything outside of a vessel. (2) Referring specifically to an ‘outboard’ motor.
Outhaul: A line that controls sail shape, specifically the draft of a sail.
Turning a sailing vessel through the wind, past the angle necessary to maintain a close-hauled course. Detrimental to making progress upwind.
Passageway: Any hallway found inside a ship.
Pennant: A triangular flag.
Pier: A structure build overtop of the water, where vessels may dock.
Pilot: A person, or navigator, with specialized knowledge of a particular area.
One half of a fitting designed to attach a rudder to a hull.
Piracy: An act of criminal activity on the high seas.
Anyone who participates in piracy.
A type of spectacular end-for-end capsize, in which the stern is catapulted over the bow.
Plane: When a vessel skims over the surface of the water rather than moving through it.
Point up: To change direction such that the bow is pointed more towards the wind.
Points of sail:
Set of terminology
that refers to the direction of travel in relationship to the wind.
Port tack: Sailing with the wind coming over the port side of the vessel.
Preventer: A sail control line that prevents accidental jibes.
Propeller: A fan shaped apparatus that converts rotational force into forward thrust.
Propeller walk: The tendency for a propeller to push a vessel sideways instead of forward or backward.
The mechanical advantage gained from the use of line
Radar: Short for radio detection and ranging. A system designed to send radio signals, and interpret their reflections as an image on a screen.
Measurement of fore/aft angle of a mast.
Rating: Refers to the PHRF handicap number assigned to a vessel.
A block that will spin in one direction, but not the other. Designed to provide friction in the loaded direction so as to make handling a line easier.
Reaching: Sailing on a course at about 90° to the true wind direction.
Ready about: Warning issued to the crew, informing them that a tack or a jibe is in progress.
Reef: Method of temporarily reducing sail area.
Reeve: Act of running a line through a series of blocks.
Reeving eye: A type of eye splice designed to facilitate the reeving of a line through a mast, or series of blocks.
Regatta: A series of sailing races.
The system of lines, spars, and hardware on a sailing vessel.
Rogue wave: A wave that is significantly larger than the present sea state, often coming from an unexpected direction of travel.
Roll: The side to side movement of a vessel.
The part of a ship’s steering system that makes contact with the water.
Run: Point of sail approximately 160° from the wind direction.
A piece of fabric attached to a vessel such that it causes the wind to exert force on a vessel.
Sail loft: A large flat space suited for working on sails.
Sail maker: A craftsman who works with sails.
Scandalize: A method used to expediently reduce sail area, without properly reefing or furling.
Schooner: A sailing vessel with fore and aft masts of similar height.
Screecher: A crossover sail that is somewhere between a spinnaker and a genoa.
Scow: A specific type of sailing dinghy characterized by a large sail plan, and wide beam.
Screw: Another term for a propeller.
Scud: Low lying clouds, particularly those observed in bad weather.
Scudding: A vessel carried along by a fierce storm.
Scull(ing): A method of providing forward momentum that involves rocking a boat from side to side, with synchronized movement of the rudder back and forth.
Scuttle: Method of sinking a ship a ship, usually by opening seacocks to flood the vessel with water.
Scuttlebutt: A drinking fountain found aboard a ship, slang for gossip.
Sea anchor: A canvas anchor deployed in deep water, designed to stabilize a ship in heavy weather by keeping her pointed into the wind and waves.
Sea state: Overall surface conditions of a large area of water.
Seacock: A specific type of valve that allows seawater to enter through the hull of a boat.
Sextant: A navigational instrument that uses celestial bodies (stars, planets etc.) to measure a ships latitude and longitude.
Shakedown cruise: A test voyage to measure the performance of a ship or her crew.
A line used to control the shape of a sail in reference to the wind direction.
Shoal: An area of shallow water.
Shoal draught: A ship with an unusually shallow draft, being able to navigate much shallower water than would be otherwise possible.
The lines or cables that hold a mast up from the sides.
A flag that is representative of a letter, word, or some other semantic meaning.
Sinking: Present participle of the verb “to sink”, of which it is common knowledge among sailors that all boats are sinking, some merely faster than others.
Skeg: A downward projection from the hull that protects the rudder from damage.
A lightweight, high performance sailing dinghy, capable of easily planing across the water at high speeds.
Skipper: Another word for the captain of a ship.
Slip: A designated space for a boat to dock in.
Sloop: A medium sized sailboat with one mast, and sails fore and aft.
A device that uses sound to range and image underwater objects.
that approaches from the southwest.
Any pole that supports a sail.
A line securing a vessel to a dock, particularly one that prevents fore and aft movement.
A method of joining two lines together, or creating an eye at the end of a line, by unraveling the braid and recombining into one continuous piece.
A spar used in conjunction with shrouds to help stabilize the mast.
A short vertical pole through which life lines
are run to keep crew from falling overboard.
A system of line or wire that is designed to support the mast, and is not normally adjusting while under sail.
Starboard tack: Sailing with the wind coming over the starboard side of the vessel.
Similar to a shroud, a part of the standing rigging
that helps support the mast.
Staysail: A sail attached to a forestay, usually smaller than a jib or genoa.
Steaming light: A light displayed at night, indicating that a sailing vessel is under motorized power.
Steerage: Act of steering a vessel.
Stopper knot: A knot that keeps a line from passing through a hole or block.
Stow: To put away or store in such a way as to make seaworthy.
A popular, beach launched sailing dinghy with a lateen rig.
Tack: The forward most corner of a sail.
Tacking: A zigzag course to achieve a net upwind direction.
Tacking duels: A series of complex maneuvers between two boats tacking to windward, with the end goal of gaining an aerodynamic advantage over a competitor.
Small strip of yarn or fabric attached to a sail, used as an indicator of air flow.
Thwart: A bench seat.
A lever attached to the rudder used for steering.
An extension attached to the tiller to aid in gaining better helm feel, and body positioning.
Tonnage: The total weight of a vessel.
Topping lift: A line designed to hold a spar aloft.
Transom: The aft most wall, or bulkhead of a vessel.
A fitting that slides from side to side on a line or track. Commonly used as an attachment point for the mainsheet.
Small adjustments made to sails in order to maximize their efficiency.
Trimaran: A sailing vessel with three hulls.
True north: The direction towards the Earth’s geographic north pole.
Two threaded bolts encased within a frame, used to put tension onto a vessels standing rigging.
Turning turtle: A full 180° capsize, when a vessel’s mast is pointed directly towards the bottom of the sea floor.
Upwind: The direction towards which the wind is coming from, from a given reference point.
Vessel: Any craft designed for movement through or on the water.
Wake: Turbulent water left behind a vessel in motion.
Wash: Waves created by a vessel in motion.
Waterline: Where the hull of a ship meets the surface of the water.
Waypoint: An intermediate point defined by a set of navigational coordinates.
Weigh anchor: To pull up an anchor.
Wetted area: The surface area of a hull immersed in water.
An alternative steering device to a tiller, usually found on larger vessels.
Spar used to hold a large jib or genoa outboard when sailing downwind.
Windage: Net wind resistance of a boat.
Windlass: A winch mounted on a horizontal axis used to weigh anchor on larger vessels.
Windward: A direction upwind from a point of reference.
Yacht: A recreational vessel, usually of intermediate to large size.
Yawl: A two masted sailing vessel, specifically with the aft mast behind the helm.