Abeam – At right angles to, or beside, the boat 
Aboard – On or in the boat 
Adrift: Afloat and unattached in any way to the shore or seabed. It may also imply that a vessel is not anchored and not under control, therefore goes where the wind and current take her, (loose from moorings, or out of place). Also refers to any gear not fastened down or put away properly. It can also be used to mean “absent without leave”.
Aft – towards the stern of the boat; to move aft is to move back 
Aground – When the hull or keel is against the ground 
Anchor – An object designed to grip the ground, under a body of water, to hold the boat in a selected area 
Anchorage — a place for anchoring 
Anchor light: White light displayed by a ship at anchor. Two such lights are displayed by a ship over 150 feet (46 m) in length.
Apparent wind :The perceived wind direction experienced on a moving boat. 
Astern – in the direction of, or behind, the stern
As the crow flies: A direct line between two points (which might cross land) which is the way crows travel rather than ships which must go around land.


Backstay: A wire support for the mast, usually running from the stern to the head of the mast. 
Backwinded: when the wind hits the leeward side of the sails 
Bail: to remove water from the boat 
Ballast: weight in the lower portion of a boat, used to add stability (In a multihull – useless crew on other boats.) 
Bareboat: Bareboat is to sailing as free fall is to skydiving. Essentially it is sailing a yacht on your own. It is exhilarating, exciting and the rush of freedom is infectious
Barber Hauler: A line attached to the jib or jib sheet, used to adjust the angle of sheeting by pulling the sheet toward the centerline of the boat. 
Batten: A thin wooden or plastic strip inserted into a pocket on the back part (leech) of a sail, to assist in keeping its form 
Beam: the greatest width of the boat, usually in the middle. 
Beam reach: a point of sail where the boat is sailing at a right angle to the apparent wind. 
Bearing: a compass direction from one point to another 
Beating (Close Hauled, On the Wind): Sailing toward the wind source, or against the wind, with the sails pulled in all the way, tacking as you go, to reach a destination upwind. 
Berth: sleeping bunk aboard the boat 
Bight: a loop in a rope -or- a bend in the shoreline 
Bilge: the lowest part of a boat, designed to collect water that enters the boat 
Binnacle: compass stand 
Bitter End: the final inboard end of chain or line 
Blanketing: a tactical manuever whereby a boat uses its sails to blanket the competitor’s wind, slowing him down. 
Block: a pulley 
Bluewater Sailing: open ocean sailing, as opposed to being in a lake or sound 
Boat Hook: a device designed to catch a line when coming alongside a pier or mooring. 
Bobstay: Wire stay underneath the bowsprit; helps to counteract the upward pull exerted by the forestay. 
Boom: the horizontal spar to which the foot of a sail is attached. 
Boom Gallows:  Piece of nice teak that is made into a board about the width of the cockpit of a sailboat that supports a boom when the sail is lowered.
Boom Vang: A system used to hold the boom down, particularly when boat is sailing downwind, so that the mainsail area facing the wind is kept to a maximum. Frequently extends from the boom to a location near the base of the mast. Usually tackle- or lever-operated. 
Boom: the horizontal spar on the bottom of the mainsail behind the mast. 
Boot Stripe : a different color strip of paint at the waterline 
Boot top: A stripe near the waterline. 
Bow: forward end of a boat 
Bowsprit: A short spar extending forward from the bow. Normally used to anchor the forestay. 
Breast line – a docking line going at approximately a right angle from the boat to the dock 
Bridge deck: The transverse partition between the cockpit and the cabin. 
Bridle: A short length of wire with a line attached at the midpoint. A bridle is used to distribute the load of the attached line. Often used as boom travelers and for spinnaker down hauls. 
Bright Work: varnished woodwork or polished metal 
Broach: a turning or swinging of the boat that puts the beam against the waves, creating a danger of swamping or capsize 
Broad Reach: a point of sail where the boat is sailing away from the wind, but not directly downwind 
Bulkhead:An interior partition commonly used to stiffen the hull that separates one part of the vessel from another. May be watertight. 
Bulwark: A vertical extension above the deck designed to keep water out and to assist in keeping people in. 
Bulwarks: rail around the deck 
Bunk: Sleeping accommodation
Buoy: An anchored float marking a position or for use as a mooring 
By the Lee: Sailing downwind with the wind blowing over the leeward side of the boat, increasing the possibility of an unexpected jibe.


Cabin: Bedroom on a yacht
Cape Horn fever:The name of the fake illness a malingerer is pretending to suffer from.
Capsize: When a ship or boat lists too far and rolls over, exposing the keel. On large vessels, this often results in the sinking of the ship
Catamaran: A boat with two hulls
Chart: The map on which you check your position and plan your next voyage
Cleat: A stationary device used to secure a rope aboard a vessel.
Crow’s Nest: A shelter or platform fixed at the masthead of a vessel as a place for a lookout to stand.
Cut of his jib: The “cut” of a sail refers to its shape. Since this would vary between ships, it could be used both to identify a familiar vessel at a distance, and to judge the possible sailing qualities of an unknown one.
Cutter: A single-masted boat, with two or more headsails.


Decks: the structures forming the approximately horizontal surfaces in the ship’s general structure. Unlike flats, they are a structural part of the ship.
Deck hand: A person whose job involves aiding the deck supervisor in (un)mooring, anchoring, maintenance, and general evolutions on deck.
Dinghy: Designed for quick trips between ship and shore. The small inflatable boat attached to the yacht
Dog watch: A short watch period, generally half the usual time (e.g. a two hour watch between two four hour ones). Such a watch might be included in order to slowly rotate the system over several days for fairness, or to allow both watches to eat their meals at approximately normal times.
Draft: The minimum depth of water needed to float your boat


Fathom: A unit of length equal to 6 feet (1.8 m), roughly measured as the distance between a man’s outstretched hands.
Fender: An air or foam filled bumper used in boating to keep boats from banging into docks or each other.
First Mate: The Second in command of a ship.
Fly by night: A large sail used only for sailing downwind, requiring little attention.
Following sea: Wave or tidal movement going in the same direction as a ship.
Foot: The bottom of a sail.
Footloose: If the foot of a sail is not secured properly, it is footloose, blowing around in the wind.
Foredeck: The deck at the forward part of the vessel.
Forestays: Long lines or cables, reaching from the front of the vessel to the mast heads, used to support the mast.
Foul-Weather Gear (aka foulies, aka Oilskins): Protective garment that is intended to keep the sailor dry and warm in bad weather.
Furl: To roll or wrap a sail around the mast or spar to which it is attached.


Global Positioning System (GPS): A satellite based radionavigation system providing continuous worldwide coverage. It provides navigation, position, and timing information to air, marine, and land users.


Halyard: Originally, ropes used for hoisting a spar with a sail attached; today, a line used to raise the head of any sail.
Hand over fist: To climb steadily upwards, from the motion of a sailor climbing shrouds on a sailing ship (originally “hand over hand”).
Handsomely: With a slow even motion, as when hauling on a line “handsomely.”
Hank: A fastener attached to the luff of the headsail that attaches the headsail to the forestay. Typical designs include a bronze or plastic hook with a spring-operated gate, or a strip of cloth webbing with a snap fastener.
Harbor: A harbor or harbour, or haven, is a place where ships may shelter from the weather or are stored. Harbours can be man-made or natural.
Haul wind: To point the ship so as to be heading in the same direction as the wind, generally not the fastest point of travel on a sailing vessel.
Head: The toilet or latrine of a vessel, which for sailing ships projected from the bows.
Headsail: Any sail flown in front of the most forward mast.
Heave: A vessel’s transient up-and-down motion.
Heaving to: To stop a sailing vessel by lashing the helm in opposition to the sails. The vessel will gradually drift to leeward, the speed of the drift depending on the vessel’s design.
Heave down:Turn a ship on its side (for cleaning).
Heeling: Heeling is the lean caused by the wind’s force on the sails of a sailing vessel.
Helmsman: A person who steers a ship.
Hogging or hog: The distortion of the hull where the ends of the keel are lower than the center.
Hold: In earlier use, below the orlop deck, the lower part of the interior of a ship’s hull, especially when considered as storage space, as for cargo. In later merchant vessels it extended up through the decks to the underside of the weather deck.
Holiday: A gap in the coverage of newly applied paint, slush, tar or other preservative.
Holystone: A chunk of sandstone used to scrub the decks. The name comes from both the kneeling position sailors adopt to scrub the deck (reminiscent of genuflection for prayer), and the stone itself (which resembled a Bible in shape and size).
Horn: A sound signal which uses electricity or compressed air to vibrate a disc diaphragm.
Horse: Attachment of sheets to deck of vessel (Main-sheet horse).
Hounds: Attachments of stays to masts.HullThe shell and framework of the basic flotation-oriented part of a ship.
Hydrofoil: A boat with wing-like foils mounted on struts below the hull.


Icing: A serious hazard where cold temperatures (below about -10°C) combined with high wind speed (typically force 8 or above on the Beaufort scale) result in spray blown off the sea freezing immediately on contact with the ship.
Idlers: Members of a ship’s company not required to serve watches. These were in general specialist tradesmen such as the carpenter and the sailmaker.
In Irons: When the bow of a sailboat is headed into the wind and the boat has stalled and is unable to maneuver.
In the offing: In the water visible from on board a ship, now used to mean something imminent.


Jack: Either a flag, or a sailor. Typically the flag was talked about as if it were a member of the crew. Strictly speaking, a flag is only a “jack” if it is worn at the jackstaff at the bow of a ship.
Jacklines or Jack Stays: Lines, often steel wire with a plastic jacket, from the bow to the stern on both port and starboard. The Jack Lines are used to clip on the safety harness to secure the crew to the vessel while giving them the freedom to walk on the deck.
Jack Tar: A sailor dressed in ‘square rig’ with square collar. Formerly with a tarred pigtail.
Jib: A triangular staysail at the front of a ship.
Jibe: A sailing maneuver whereby a sailing vessel reaching downwind turns its stern through the wind, which then exerts its force from the opposite of the vessel.
Jigger-mast: The fourth mast, although ships with four or more masts were uncommon, or the aft most mast where it is smallest on vessels of less than four masts.
Jollies:Traditional Royal Navy nickname for the Royal Marines.
Junk: Old cordage past its useful service life as lines aboard ship. The strands of old junk were teased apart in the process called picking oakum.


Keel: A lengthwise timber or steel structure along the base of a ship, supporting the framework of the whole, in some vessels extended downwards as a ridge to increase stability. It serves as the central structural basis of the hull.
Keelhauling: Maritime punishment: to punish by dragging under the keel of a ship.
Kelson:The timber immediately above the keel of a wooden ship.
Ketch: A fore-and-aft rigged vessel similar to a yawl but with a larger mizzen sail and with the mizzenmast stepped farther forward of the helm.
Kissing the gunner’s daughter: bend over the barrel of a gun for punitive spanking with a cane or cat.
Know the ropes: A sailor who ‘knows the ropes’ is familiar with the miles of cordage and ropes involved in running a ship.


Ladder: On board a ship, all “stairs” are called ladders, except for literal staircases aboard passenger ships. Most “stairs” on a ship are narrow and nearly vertical, hence the name. Believed to be from the Anglo-Saxon word hiaeder, meaning ladder.
Laker: Great Lakes slang for a vessel who spends all its time on the 5 Great Lakes.
Land lubber: A person unfamiliar with being on the sea.
Lanyard: A rope that ties something off.
Lateral System: A system of aids to navigation in which characteristics of buoys and beacons indicate the sides of the channel or route relative to a conventional direction of buoyage (usually upstream).
Lay down:To lay a ship down is to begin construction in a shipyard.
League: A unit of length, normally equal to three nautical miles.
Leech: The aft or trailing edge of a fore-and-aft sail; the leeward edge of a spinnaker; a vertical edge of a square sail. The leech is susceptible to twist, which is controlled by the boom vang and mainsheet.
Leehelm: If the helm was centered, the boat would turn away from the wind (to the lee). Consequently, the tiller must be pushed to the lee side of the boat in order to make the boat sail in a straight line.
Lee side: The side of a ship sheltered from the wind (opposite the weather side or windward side).
Lee shore: A shore downwind of a ship. A ship which cannot sail well to windward risks being blown onto a lee shore and grounded.
Leeway: The angle that a ship is blown leeward by the wind. See also weatherly.
Leeward: In the direction that the wind is blowing towards.
Let go and haul: An order indicating that the ship is in line with the wind.
Lifeboat: A small steel or wood boat located near the stern of a vessel. Used to get the crew to safety if something happens to the mothership.
Line: The correct nautical term for the majority of the cordage or “ropes” used on a vessel. A line will always have a more specific name, such as mizzen topsail halyard, which describes its use.
List: The vessel’s angle of lean or tilt to one side, in the direction called roll.
Loaded to the gunwales: Literally, having cargo loaded as high as the ship’s rail; also means extremely drunk.
Lubber’s line: A vertical line inside a compass case indicating the direction of the ship’s head.
1- The forward edge of a sail.
2- To head a sailing vessel more towards the direction of the wind.
1- When a sailing vessel is steered far enough to windward that the sail is no longer completely filled with wind (the luff of the sail is usually where this first becomes evident).
2- Loosening a sheet so far past optimal trim that the sail is no longer completely filled with wind.
3- The flapping of the sail(s) which results from having no wind in the sail at all.
Lying ahull: Waiting out a storm by dousing all sails and simply letting the boat drift.


Mainmast (or Main):The tallest mast on a ship.
Mainsheet: Sail control line that allows the most obvious effect on mainsail trim. Primarily used to control the angle of the boom, and thereby the mainsail, this control can also increase or decrease downward tension on the boom while sailing upwind, significantly affecting sail shape. For more control over downward tension on the boom, use a boom vang.
Man of war: A warship from the age of sail.
Man overboard!: A cry let out when a seaman has gone overboard.
Marina: A docking facility for small ships and yachts.
Marines Soldiers afloat: Royal Marines formed as the Duke of York and Albany’s Maritime Regiment of Foot in 1664 with many and varied duties including providing guard to ship’s officers should there be mutiny aboard. Sometimes thought by seamen to be rather gullible, hence the phrase “tell it to the marines”.
Mast: A vertical pole on a ship which supports sails or rigging.
Masthead: A small platform partway up the mast, just above the height of the mast’s main yard. A lookout is stationed here, and men who are working on the main yard will embark from here. See also Crow’s Nest.
Master: Either the commander of commercial vessel, or a senior officer of a naval sailing ship in charge of routine seamanship and navigation but not in command during combat.
Mizzenmast (or Mizzen):The third mast on a ship.
Mizzen staysail: Sail on a ketch or yawl, usually lightweight, set from, and forward of, the mizzen mast while reaching in light to moderate air.
Monkey fist: A ball woven out of line used to provide heft to heave the line to another location. The monkey fist and other heaving-line knots were sometimes weighted with lead.
Moor: To attach a boat to a mooring buoy or post. Also, to a dock a ship.


Navigation rules: Rules of the road that provide guidance on how to avoid collision and also used to assign blame when a collision does occur.
No room to swing a cat:The entire ship’s company was expected to witness floggings, assembled on deck. If it was very crowded, the bosun might not have room to swing the “cat o’ nine tails” (the whip).


Outhaul: A line used to control the shape of a sail.
Outward bound: To leave the safety of port, heading for the open ocean.
Overfall: Dangerously steep and breaking seas due to opposing currents and wind in a shallow area.
Overhaul: Hauling the buntline ropes over the sails to prevent them from chaffing.
Overhead: The “ceiling,” or, essentially, the bottom of the deck above you.
Overreach: When tacking, to hold a course too long.
Over the barrel: Adult sailors were flogged on the back or shoulders while tied to a grating, but boys were beaten instead on the posterior (often bared), with a cane or cat, while bending, often tied down, over the barrel of a gun, known as (kissing) the gunner’s daughter.
Ox-Eye: A cloud or other weather phenomenon that may be indicative of an upcoming storm.


Pilot: Navigator. A specially knowledgeable person qualified to navigate a vessel through difficult waters, e.g. harbour pilot etc.
Pitch: A vessel’s motion, rotating about the beam axis, so the bow pitches up and down.
Pitchpole: To capsize a boat end over end, rather than by rolling over.
Poop deck: A high deck on the aft superstructure of a ship.
1-Swamped by a high, following sea.
Port: The left-hand side of the ship facing forward (formerly Larboard). Denoted with a red light at night.
Preventer: (Gybe preventer, Jibe preventer)A sail control line originating at some point on the boom leading to a fixed point on the boat’s deck or rail (usually a cleat or pad eye) used to prevent or moderate the effects of an accidental jibe.
Propeller walk or prop walk:Tendency for a propeller to push the stern sideways. In theory a right hand propeller in reverse will walk the stern to port.
Prow: A poetical alternative term for bows.


Quarterdeck: The aftermost deck of a warship. In the age of sail, the quarterdeck was the preserve of the ship’s officers.


Radar: Acronym for RAdio Detection And Ranging. An electronic system designed to transmit radio signals and receive reflected images of those signals from a “target” in order to determine the bearing and distance to the “target”.
Radar reflector: A special fixture fitted to a vessel or incorporated into the design of certain aids to navigation to enhance their ability to reflect radar energy. In general, these fixtures will materially improve the visibility for use by vessels with radar.
Range lights: Two lights associated to form a range (a line formed by the extension of a line connecting two charted points) which often, but not necessarily, indicates the channel centerline. The front range light is the lower of the two, and nearer to the mariner using the range. The rear light is higher and further from the mariner.
Reach: A point of sail from about 60° to about 160° off the wind. Reaching consists of “close reaching” (about 60° to 80°), “beam reaching” (about 90°) and “broad reaching” (about 120° to 160°).Red DusterTraditional nickname for the Civil Red Ensign.Reduced catA light version on the cat o’nine tails for use on boys; also called “boys’ pussy”.
Reduced cat: A light version on the cat o’nine tails for use on boys; also called “boys’ pussy”.
1-Reef: To temporarily reduce the area of a sail exposed to the wind, usually to guard against adverse effects of strong wind or to slow the vessel.
2-Reef: Rock or coral, possibly only revealed at low tide, shallow enough that the vessel will at least touch if not go aground.
Reef points: Small lengths of cord attached to a sail, used to secure the excess fabric after reefing.
Rigging: The system of masts and lines on ships and other sailing vessels.
Righting couple: The force which tends to restore a ship to equilibrium once a heel has altered the relationship between her centre of buoyancy and her centre of gravity.
Roll: A vessel’s motion rotating from side to side, about the fore-aft axis. List (qv) is a lasting tilt in the roll direction.
Rolling-tackle: A number of pulleys, engaged to confine the yard to the weather side of the mast; this tackle is much used in a rough sea.
The Ropes: Refers to the lines in the rigging.
Rope’s end: A summary punishment device.
Running rigging: Rigging used to manipulate sails, spars, etc. in order to control the movement of the ship. Cf. standing rigging.


Schooner: A sailing ship with two or more masts, typically with the foremast smaller than the mainmast.
Sloop: A one-masted sailing boat with a mainsail and jib rigged fore and aft.
Starboard: The right-hand side of the ship facing forward. Denoted with a green light at night.


Taking the wind out of his sails: To sail in a way that steals the wind from another ship. cf. overbear.
Three sheets to the wind: On a three-masted ship, having the sheets of the three lower courses loose will result in the ship meandering aimlessly downwind. Also, a sailor who has drunk strong spirits beyond his capacity.
Toe the line or Toe the mark: At parade, sailors and soldiers were required to stand in line, their toes in line with a seam of the deck.
Travellers: Small fittings that slide on a rod or line. The most common use is for the inboard end of the mainsheet; a more esoteric form of traveller consists of “slight iron rings, encircling the backstays, which are used for hoisting the top-gallant yards, and confining them to the backstays”.
Transom: A more or less flat surface across the stern of a vessel.
Trick: A period of time spent at the wheel (“my trick’s over”).
Trim: Relationship of ship’s hull to waterline.
Turtling: When a sailboat (in particular a dinghy) capsizes to a point where the mast is pointed straight down and the hull is on the surface resembling a turtle shell.


Under the weather: Serving a watch on the weather side of the ship, exposed to wind and spray.
Under way: A vessel that is not at anchor, or made fast to the shore, or aground.
Underwater hull or underwater ship:The underwater section of a vessel beneath the waterline, normally not visible except when in drydock.


Vanishing angle: The maximum degree of heel after which a vessel becomes unable to return to an upright position.


Wake: Turbulence behind a ship.
Watch: A period of time during which a part of the crew is on duty. Changes of watch are marked by strokes on the ship’s bell.
Watercraft: Water transport vessels. Ships, boats, personal water craft.
Weatherhelm: If the helm was centered, the boat would turn towards the wind (weather). Consequently, the tiller must be pulled to the windward side of the boat in order to make the boat sail in a straight line.
Weather side: The weather side of a ship is the side exposed to the wind.
Weigh anchor: To heave up (an anchor) preparatory to sailing.
White Horses: Waves in wind strong enough to produce foam or spray on the wave tops.
Wide berth: To leave room between two ships moored (berthed) to allow space for maneuver.
Windage: Wind resistance of the boat.
Windbound: A condition wherein the ship is detained in one particular station by contrary winds.
Windward: In the direction that the wind is coming from.
Windlass: A winch mechanism, usually with a horizontal axis. Used where mechanical advantage greater than that obtainable by block and tackle was needed (such as raising the anchor on small ships). Modern sailboats use an electric “Windlass” to raise the anchor.


Yaw: A vessel’s motion rotating about the vertical axis, so the bow yaws from side to side.
Yawl: A two-masted fore-and-aft-rigged sailing boat with the mizzenmast stepped far aft of the helm so that the mizzen boom overhangs the stern.