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Glossary of nautical terms (M–Z)
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This glossary of nautical terms is an alphabetical listing of terms and expressions connected with ships, shipping, seamanship and navigation on water (mostly though not necessarily on the sea). Some remain current, while many date from the 17th to 19th centuries. The word nautical derives from the Latin nauticus, from Greek nautikos, from nautēs: "sailor", from naus: "ship".
Further information on nautical terminology may also be found at Nautical metaphors in English, and additional military terms are listed in the Multiservice tactical brevity code article. Terms used in other fields associated with bodies of water can be found at Glossary of fishery terms, Glossary of underwater diving terminology, Glossary of rowing terms, and Glossary of meteorology.
This glossary is split into two articles:
- terms starting with the letters A to L are at Glossary of nautical terms (A–L)
- terms starting with the letters M to Z are at Glossary of nautical terms (M–Z).
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M
- mack
- A structure which combines the radar mast and the exhaust stack of a surface ship, thereby saving valuable deck space.[citation needed]
- Mae West
- A Second World War personal flotation device used to keep people afloat in the water; named after the 1930s actress Mae West, well known for her large bosom.
- magazine
The ammunition storage area aboard a warship.
- magnetic bearing
- An absolute bearing using magnetic north.
- magnetic north
- The direction towards the North Magnetic Pole. Varies slowly over time.
- maiden voyage
- The first voyage of a ship in its intended role, i.e. excluding trial trips.
- Maierform bow
- A V-shaped bow introduced in the late 1920s which allowed a ship to maintain a given speed with less power, improved seakeeping, increased reserve buoyancy, reduced pitching movements, and improved propeller immersion to increase performance in rough seas.
- main
- The high sea; the open ocean.
- main deck
- The uppermost continuous deck extending from bow to stern.
- mainbrace
- Either of the braces attached to the yard of the mainsail (the largest and lowest sail on the mainmast) on a square-rigged vessel.
- mainmast
1. The tallest mast on a ship[1] with more than one mast, especially the tallest mast on a full-rigged ship.
- 2. On a ship with more than one mast, the second mast from the bow.
- mainmast head
- The top of a sailing vessel's mainmast.
- mainmastman
- A sailor assigned to the mainmast.
- mains
- The main brails on the mainsail.[2]
- mainsheet
- A 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, a boom vang may be used.
- mainstay
- The stay running from the top of the mainmast to the bottom of the foremast, or from the top of the foremast to the ship's stem.
- making way
- When a vessel is moving under its own power.
- man-of-war
A warship from the Age of Sail.
- man overboard
- 1. An emergency call that alerts the crew that someone aboard has gone overboard into the water and must be rescued.
- 2. A person who has fallen into the water from a ship or boat – the object of the resulting rescue attempt.
- man the rails
- To station the crew of a naval vessel along the rails and superstructure of the vessel as a method of saluting or rendering honors.
- man the yards
- To have all of the crew of a sailing vessel not required on deck to handle the ship go aloft and spread out along the yards. Originally used in harbors to display the whole crew to harbor authorities and other ships present to show that the vessel's guns were not manned and hence her intentions were peaceful, manning the yards has since become a display used in harbor during celebrations and other special events.
- manifest
- A document listing the cargo, passengers, and crew of a ship for the use of customs and other officials.
- Marconi rig
- An archaic term for Bermuda rig. The mainsail is triangular, rigged fore-and-aft with its luff fixed to the mast. The foresail (jib) is a staysail hanked onto the forestay. Refers to the similarity of the tall mast to a radio aerial.
- marina
- A docking facility for small ships and yachts.
- marine
- 1. A soldier trained for service afloat in a (primarily) infantry force that specializes in naval campaigns and subordinated to a navy or a separate naval branch of service rather than to an army. Often capitalized (e.g. a Marine or the Marines). Notable examples are the United Kingdom's 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 a mutiny aboard, and the US Marine Corps, formed in 1775 as a separate naval service alongside the US Navy. It is incorrect, and often viewed by marines as offensive, to refer to a marine as a "soldier" or "infantryman", as these terms refer to personnel of an army rather than those of a marine force. It also is incorrect, and sometimes considered offensive by both merchant mariners and marines, to refer to merchant mariners as "merchant marines", because merchant mariners are civilian sailors responsible for operating merchant ships and are not marines. Marines sometimes are thought by seamen to be rather gullible, hence the phrase "tell it to the marines", meaning that one does not believe what is being said.
- 2. An alternative term for a navy, uncommon in English but common in other languages.
- 3. Of or pertaining to the sea (e.g. marine biology, marine insurance, marine salvage).
- 4. A painting representing a subject related to the sea.
- marine sandglass (or glass)
- An hourglass-like timekeeping instrument used aboard ships from at least the 14th century until reliable mechanical timepieces replaced it in the early 19th century. Marine sandglasses measured the passage of time in 30-minute increments to regulate time on watch, to measure a boat's speed, and to assist in determining a ship's position by measuring the time elapsed while she was on a given course.
- mariner
- A sailor.
- maritime
- 1. Of or related to the sea (e.g., maritime activities, maritime law, maritime strategy).
- 2. Bordering on the sea (e.g., maritime provinces, maritime states).
- 3. Living in or near the sea (e.g., maritime animals).
- 4. Of or relating to a mariner or sailor.
- marlinspike
- A tool used in ropework for tasks such as unlaying rope for splicing, untying knots, or forming a makeshift handle.
- mast
- A vertical pole on a ship that supports sails or rigging. If a wooden multi-part mast, this term applies specifically to the lowest portion.
- mast case
- A yachtsman's tabernacle. The iron fitting in which the heel of the mast is mounted.[2]
- Mast partner
- The reinforced area of the deck surrounding the hole through which a mast passes as it rises from its step (usually on the keel) to the above-deck area[3]
- mast step
- The place in the hull where the lowest point of a mast rests, taking the weight of the mast and the thrust imposed by the tension of the rigging, and preventing lateral and fore and aft movement of the bottom of the mast. With a wooden hull and mast, this is usually achieved by having a socket cut in the top of the keelson, a floor or some other major structural component. A tenon cut into the bottom of the mast sits snugly in the socket.[4] With a deck-stepped aluminium mast, the step may consist of a metal fitting bolted to the deck, to which bolts a matching fitting at the bottom of the mast.
- mast stepping
- The process of raising a mast.
- 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.
- masthead light
- A white running light displayed at the front of a vessel.
- master
- 1. The captain of a commercial vessel.
- 2. A senior officer of a naval sailing ship in charge of routine seamanship and navigation but not in command during combat.
- 3. (master) A former naval rank.
- master-at-arms
- A non-commissioned officer responsible for discipline on a naval ship. Standing between the officers and the crew, commonly known in the Royal Navy as "the Buffer".[citation needed]
- matelot
- A traditional Royal Navy term for an ordinary sailor.
- material
- Military equipages of all descriptions for the naval services. The bombs, blankets, beans, and bulletins of the Navy and Marine Corps. Taken from Nelson's British navy as the US services became professional. See also materiel – military supplies, equipment and weapons.
- Mediterranean mooring
A method of mooring stern-to.
- merchant marine
- A collective term for all merchant ships registered in a given country and the civilians (especially those of that nationality) who man them; the ships and personnel in combination are said to constitute that country's merchant marine. Called the merchant navy in the United Kingdom and some other countries.
- merchant mariner
- A civilian officer or sailor who serves in the merchant marine. Sometimes such personnel are incorrectly called "merchant marines", but both merchant mariners and marines frown on this term; although merchant mariners are part of the merchant marine, they are civilians and are not in any way marines, which are a specialized type of military personnel.
- A name bestowed upon the merchant marine of the United Kingdom by King George V, and since adopted by some other countries as well. The merchant navy's personnel are civilians, and the term "merchant navy" does not imply that they or their ships are a part of the navy. Synonymous with the term merchant marine.
- merchantman
- A merchant ship - any non-naval passenger- or cargo-carrying vessel, including cargo ships, tankers, and passenger ships but excluding troopships.
- mess
1. An eating place aboard a ship.
- 2. A group of crew who live and eat together.
- mess deck catering
- A system of catering in which a standard ration is issued to a mess supplemented by a money allowance, which the mess may use to buy additional victuals from the purser's stores or elsewhere. Each mess was autonomous and self-regulating. Seaman cooks, often members of the mess, prepared the meals and took them, in a tin canteen, to the galley to be cooked by the ship's cooks. As distinct from "cafeteria messing" where food is issued to an individual hand, which is now the general practice.
- metacenter
- The midway point between a vessel's center of buoyancy when upright and her center of buoyancy when tilted.
- metacentric height (GM)
- A measurement of the initial static stability of a vessel afloat, calculated as the distance between her center of gravity and her metacenter. A vessel with a large metacentric height rolls more quickly and therefore more uncomfortably for people on board; a vessel with a small metacentric height will roll sluggishly and may face a greater danger of capsizing.
- Middle Passage
- The portion of the triangular trade pattern of the late 16th through the early 19th centuries in the Atlantic Ocean in which slaves were transported from Africa to the Americas. In the terminology of the slave trade itself, the Middle Passage linked the First Passage (the delivery from Europe of the trade goods to be used to purchase slaves) with the Final Passage (the shipment of the products of slave plantations – sugar, tobacco, cotton – to the markets of Europe).
- middles
- The middle brails on the mainsail, higher than the lowers, and lower than the mains.[2]
- midship house
- A superstructure built over the midships section of the hull, often housing the bridge and officers quarters, as well as passenger quarters aboard cargo liners. A common feature of tankers, cargo liners, and cargo ships up until the mid-20th century, when ship design moved away from the use of midship houses.
- midshipman
- 1. During the 17th century, a naval rating for an experienced seaman.
- 2. From the 18th century, a naval commissioned officer candidate.
- 3. From the 1790s, an apprentice naval officer.
- 4. From the 19th century, an officer cadet at a naval academy.
- 5. In contemporary British usage, a non-commissioned officer below the rank of lieutenant. Usually regarded as being "in training" to some degree. Also known as "Snotty". It is "the lowest form of rank in the Royal Navy" where he has authority over and responsibility for more junior ranks, yet, at the same time, relying on their experience and learning his trade from them.
- 6. In contemporary American usage, a cadet of either sex at the United States Merchant Marine Academy or the United States Naval Academy, or under contract and having sworn the Oath of Office in the Navy Reserve Officer Training Corps (NROTC) program. When plural (midshipmen), the term refers to the student body of either academy, and more formally as "the Regiment of Midshipmen" for the Merchant Marine Academy and "the Brigade of Midshipmen" for the Naval Academy, or for the NROTC unit members usually organized into battalions.
- midshipman's hitch
- An alternative to the Blackwall hitch, preferred if the rope is greasy. Made by first forming a Blackwall hitch and then taking the underneath part and placing it over the bill of the hook.[5]
- midshipman's nuts
- Broken pieces of biscuit as dessert.[6]
- midshipman's roll
- A slovenly method of rolling up a hammock transversely and lashing it endways by one clue.[6]
- midships
A shortened form of amidships, with both alternative meanings.[7]
- mile
- See nautical mile.
- military mast
- A hollow, tubular mast used in warships in the last third of the 19th century, often equipped with a fighting top armed with light-caliber guns.
- millers
- Shipboard rats
- mine
- A self-contained explosive device intended to damage or sink surface ships or submarines, designed to be placed in water and left to wait until they are triggered by the approach of, proximity of, or contact with a surface ship or submarines.
- minehunter
- A vessel designed or equipped to detect and destroy individual mines. It differs from a minesweeper, which is designed or equipped to clear areas of water of mines without necessarily detecting them first.
- minelayer
- A vessel designed or equipped to deploy (or "lay") mines.
- minesweeper
- A vessel designed or equipped to clear areas of water of mines without necessarily detecting them first. It differs from a minehunter, which is designed or equipped to detect and destroy individual mines.
- misstay
- To be "in irons" (i.e. to lose forward momentum) when changing tack.
- mizzen
- 1. A mizzen sail is a small sail (triangular or gaff) on a ketch or yawl set abaft the mizzenmast.[2]
- 2. A mizzen staysail is an occasional lightweight staysail on a ketch or yawl, set forward of the mizzenmast while reaching in light to moderate airs.[2]
- 3. A mizzenmast is a mast on a ketch or yawl, or spritsail barge. Its positioning afore of abaft the rudder post distinguishes between a ketch or a yawl. On a barge its rig determines if she is a muffie or a mulie.[2]
- mizzenmast
The third mast, or the mast aft of the mainmast, on a ship.
- mole
- A massive structure, usually of stone or concrete, used as a pier, breakwater, or causeway between places separated by water. May have a wooden structure built upon it and resemble a wooden pier or wharf, but a mole differs from a pier, quay, or wharf in that water cannot flow freely underneath it.
- molgogger
- 1. A type of roller fairlead, also known as a cage roller, with vertical and horizontal rollers, mounted on the bulwark or gunwale and used to constrain and guide a fishing net or towing cable for a net or minesweeping paravane.[8][9]
- 2. A removable or folding vertical bar or hook fitted to the bulwarks of a tug on either side to prevent the towline moving too far forward, which can endanger stability. Sometimes fitted with a roller. Also called a Norman pin.[10]
- monitor
- 1. A turreted ironclad warship of the second half of the 19th century characterized by low freeboard, shallow draft, poor seaworthiness, and heavy guns, intended for riverine and coastal operations.
- 2. In occasional 19th-century usage, any turreted warship.
- 3. A shallow-draft armored shore bombardment vessel of the first half of the 20th century, designed to provide fire support to ground troops, often mounting heavy guns.
- 4. (breastwork monitor) A 19th-century monitor designed with a breastwork to improve seaworthiness.
- 5. (river monitor) A monitor specifically designed for riverine operations, used during the 19th and 20th centuries and more recently than other types of monitor. River monitors generally are smaller and lighter than other monitors.
- monkey bridge
- A high platform above the wheelhouse offering better visibility to the operator while maneuvering.
- monkey's 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 (easily available in the form of foil used e.g. to seal tea chests from dampness) although Clifford W. Ashley notes that there was a "definite sporting limit" to the weight thus added.
- moor
- 1. To attach a boat to a mooring buoy or post.
- 2. To dock a ship.
- 3. To secure a vessel with a cable or anchor.
- mooring
A place to moor a vessel.
- mother ship
A vessel that leads, serves, or carries smaller vessels, in the latter case either releasing them and then proceeding independently or also recovering them after they have completed a mission or operation. A mother ship sometimes contrasts with a tender, which often (but not necessarily) is a vessel that supports or cares for larger vessels.
- motorsailer
- A type of motor-powered sailing vessel, typically a yacht, that can derive power from its sails or engine, independently of each other and often with both at the same time (motorsailing)
- motorsailing
- Proceeding under the power of sails and engines at the same time. In a yacht this is usually to windward and may be found more comfortable than using just sails or engines on their own.[11]
- motor ship
- A ship propelled by an internal combustion engine, usually a diesel engine.
- mould
- A template of the shape of the hull in transverse section. Several moulds are used to form a temporary framework around which a hull is built.
- moulded
- (of a timber in a wooden hull) The identifier of a measurement of a timber in a wooden hull, used, together with sided, instead of width and thickness which could be ambiguous – length, the third dimension is not ambiguous. Moulded identifies the measure across the surface of an individual timber where one side of that surface is shaped to fit the overall hull shape, as determined by the moulds. Therefore this is the dimension across the vertical sides of a keel, the athwartships face of a frame, or the fore and aft face of stem or stern post.[12]
- moulded beam
- moulded breadth
- The breadth of the hull lines at the widest point, normally at midships and measured inside the hull planking or plating. Used in some systems of tonnage measurement.[13]
- moulded depth
- The distance between the horizontal plane of the top of the keel and the top of the main deck beams at the edge of the hull. Compare with freeboard depth.[3]
- moulded dimensions
- Dimensions of a ship shown by the lines plan, generally excluding planking thickness and shell thickness.[13]
- moulded draft
- moulded draught
- Draught measured relative to the base line.[13] Compare with keel draught.
- mould loft
- Where the lines of the ship are drawn out full-size and the templates for the timbers are made.
- mousing
- Several turns of light line around the mouth of a hook, to prevent unhooking accidents.[2]
- mulie
- A barge rigged with a spritsail main, and a large gaff rigged mizzen afore the steering wheel. It is sheeted to the saddle chock.[2]
- multipurpose vessel
- A cargo ship that has fittings to carry standard shipping containers and retractable tweendecks that can be moved out of the way so that the ship can carry bulk cargo.
- multiservice tactical brevity code
- Codes used by various military forces to convey complex information in a few words.
- muster drill
- An exercise conducted by the crew of a ship prior to embarking on a voyage. Passengers are required to participate in the drill so that they can be instructed how to evacuate safely in the event of an emergency on board the ship.
- muster station
- A specific location on a vessel planned as a gathering place during an emergency or a muster drill. If a person is believed missing, all passengers must report to their muster station for a head count.
- muzzle
- Iron ban around the mast to hold the heel of the sprit.[2]
- M.S. (or MS)
- An abbreviation for motor ship, used before a ship's name.
- M.V. (or MV)
- An abbreviation for motor vessel, used before a ship's name.
- M.Y. (or MY)
- An abbreviation for motor yacht, used before a yacht's name.
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N
- name ship
- A ship whose name also is used to refer to her entire class of ships. Usually but not always the first ship of her class to be completed and enter service, in which case the term name ship can be used as a synonym for lead ship.
- natural harbour
- A body of water protected from the weather by virtue of its being mostly surrounded by land, and deep enough to provide anchorage for the vessels using it.
- narrowboat
- A type of boat designed specifically to fit the narrow canal locks of the United Kingdom.
- narrows
- A narrow part of a navigable waterway.
- nautical
- Of or pertaining to sailors, seamanship, or navigation; maritime.
- nautical chart
- A map of a sea or ocean area and adjacent coastal regions, intended specifically for navigation at sea. Nautical charts use map projections designed for easy use with hand instruments, such as the Mercator projection, and indicate depths, hazards, landmarks, aids to navigation such as buoys, and ashore facilities of interest to mariners. Nautical charts are generally originally published by government agencies such as the U.S. National Oceanic and Atmospheric Administration, and are now provided in both print form and digital for use in chartplotters.
- nautical mile
- A unit of length corresponding to approximately one minute of arc of latitude along any meridian arc. By international agreement, it is equivalent to exactly 1,852 metres (6,076 ft; 1.151 mi).
- The British system of authorizing naval construction by an annual bill in Parliament.
- 1. Sailors subordinated to a navy trained and equipped to operate ashore temporarily as an organized infantry force, but at other times responsible for the normal duties of sailors aboard ship.
- 2. A specialized, permanent force of troops subordinated to a navy and responsible for infantry operations ashore. Although more specialized than sailors trained to operate temporarily as naval infantry and bearing similarities to a marine force or marine corps, such permanent naval infantry forces often lack the full capabilities of a marine force. Naval infantry forces also usually differ from marine forces in being subordinated directly to a navy rather than to a separate branch of naval service such as a marine corps.
- All activities related to determining, plotting, and tracking the position and course of a ship in order to keep track of its position relative to land while at sea. Navigation charts have been used since ancient times, and remain in use as back-ups to modern satellite-based positioning systems. Numerous map projections including the common Mercator projection were developed specifically to make navigation at sea simple to perform with straight-edges and compasses.
A source of illumination on a vessel intended to give information to other vessels on her position, heading, or status.
- Rules of the road that provide guidance on how to avoid collision and also used to assign blame when a collision does occur.
- nay
- A reply in the negative, synonymous with "no". The opposite of "aye".
- net cutter
- 1. (Fisheries patrol), also trawlwire cutter: A device employed by the Icelandic Coast Guard during the "Cod Wars" to cut the trawling wires of foreign fishing trawlers working within Iceland's claimed exclusive fisheries zones.
- 2. (Submarine): A device, sometimes powered by explosives, mounted on the bow of a submarine to cut through anti-submarine netting.
- 3. (Torpedo): A scissors-like or pistol-powered device on the nose of a torpedo intended to assist the torpedo in breaking through torpedo nets.
- net laying ship
A type of naval auxiliary ship equipped for and primarily tasked with laying torpedo nets or anti-submarine nets to protect individual ships at anchor, harbors, or other anchorages from torpedo attack and intrusions by submarines.
- net tender
- An alternative term for a net laying ship.
- New Company ship
- A term used for a ship trading between England and ports east of the Cape of Good Hope for the English Company Trading to the East Indies, a new company chartered in 1697 to compete with the "old" East India Company. The term fell into disuse when the two companies merged in 1707.[14]
- night boat
- (United States) A type of steamboat that provided sleeping quarters for passengers on overnight voyages, as opposed to a day boat that had no need of such facilities.
- nipper
- A short rope used to bind a cable to the "messenger" (a moving line propelled by the capstan) so that the cable is dragged along, too (used where the cable is too large to be wrapped around the capstan itself). During the raising of an anchor, the nippers were attached and detached from the (endless) messenger by the ship's boys. Hence the term for small boys: "nippers".
- nock
- The throat of the mainsail.[2]
- 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).
- non-self-sustaining
- See self-sustaining.
- nun
- A type of navigational buoy, often cone-shaped, but if not, always triangular in silhouette, colored green in IALA region A or red in IALA region B (the Americas, Japan, Korea, and the Philippines). In channel marking its use is opposite that of a "can buoy".
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O
- oakum
- Any material, often tarred hemp fibres picked from old untwisted ropes, used for caulking gaps or seams between the planks of hulls.
- oar
- A pole, usually of wood, with a blade at one end and a handle at the other, which is pivoted on a fulcrum on the side of a boat to provide propulsion by pushing the blade through the water.[15]
- oar crutch
- A metal (or sometimes plastic) fitting that acts as the fulcrum point of an oar. It usually takes the form of a U-shape, with a pin underneath the bottom of the "U". The pin rotates in a socket in the boat's gunwale, and the oar rests in the "U".[16] See also rowlock.[11]
- ocean liner
- See liner.
- officer's country
- The part of a naval vessel containing the residential quarters and wardroom for commissioned officers. Officer's country is off-limits to enlisted personnel unless they are there on official business.
- offing
- The more distant part of the sea as seen from the shore, generally implying the open ocean beyond anchoring ground.
- offshore
- 1. Moving away from the shore.
- 2. (of a wind) Blowing from the land to the sea.
- 3. At some distance from the shore; located in the sea away from the coast.
- oiler
- 1. (ship) A naval auxiliary ship with fuel tanks which refuels other ships.
- 1. (occupation) The job title of a seaman holding a junior position in a ship's engineering crew, senior only to the engine room wiper.
- oilskins
Foul-weather clothing worn by sailors.
- old man
- Crew's slang for the captain, master, or commanding officer of a vessel.
- old salt
- Slang for an experienced mariner.
- on board
See aboard.
- on her own bottom
Said of a vessel making a voyage without being carried aboard another vessel; e.g. "the yacht crossed the ocean on her own bottom", or in the plural, "yachts rarely cross the ocean on their own bottoms".
- on station
- A ship's destination, typically an area to be patrolled or guarded.
- on the beach
- 1. A Royal Navy term that means "retired from the Service."[17]
- 2. On shore leave.
- on the hard
- A boat that has been hauled and is now sitting on dry land.
- open registry
- An organization that will register merchant ships owned by foreign entities, generally to provide a flag of convenience.
- ordinary
- See in ordinary.
- ordinary seaman
- 1. A seaman in the British Royal Navy in the 18th century who had between one and two years of experience at sea. Later, a formal rank in the Royal Navy for the lowest grade of seaman, now obsolete.
- 2. The second-lowest rank in the United States Navy from 1797 to 1917, between landsman and seaman. Renamed "seaman second class" in 1917.
- 3. The rating for entry-level personnel in the deck department of a ship in the United States Merchant Marine. An ordinary seaman (abbreviated "OS") is considered to be serving an apprenticeship to become an able seaman.
- ore carrier
- A type of bulk carrier specially designed to carry ore.
- oreboat
A Great Lakes term for a vessel primarily used in the transport of iron ore.
- orlop deck
- 1. The lowest deck of a ship-of-the-line.
- 2. The deck covering in the hold.
- oscar
- 1. International signal for a man overboard.
- 2. Nickname for a water rescue training dummy. See also paradummy.
- outboard
- 1. Situated outside the hull of a vessel.
- 2. Situated within a vessel but positioned away (or farther away, when contrasted with another item) from her centerline.
- 3. Farther from the hull of a ship; e.g. "the larger boat was tied up alongside the ship outboard of the smaller boat".
- 4. Farther from the pier or shore; e.g. "the tanker and cargo ship were tied up at the pier alongside one another with the tanker outboard of the cargo ship".
- 5. An outboard motor.
- 6. A vessel fitted with an outboard motor.
- outboard motor
- A motor mounted externally on the transom of a small boat. Outboard motors are often mounted in a way that makes them easily movable, such that the boat may be steered by rotating the whole motor with respect to the boat's bearing, instead of or in addition to using a rudder.
- outdrive
- The lower part of a sterndrive.
- outhaul
- A line used to control the shape of a sail.
- outrigger
- 1. Generally, any structure projecting from the side of a vessel.
- 2. Any contraposing float rigging beyond the side of a vessel to improve the vessel's stability.
- 3. A thin, long, solid hull used to stabilize the inherently unstable main hull of an outrigger canoe or a sailboat.
- 4. A variety of structures projecting from a keelboat by which the running rigging may be attached outboard of the hull.
- 5. A pole or series of poles projecting from a fishing vessel that allow the vessel to trawl with more fishing lines in the water without the lines tangling and allowing lures and bait to simulate a school of fish.
- 6. A triangular frame on a rowboat or galley that holds the rowlock away from the saxboard or gunwale to optimize leverage for the rowers. Also called a rigger.
- outward bound
- To leave the safety of port, heading for the open ocean.
- over-canvassed
- To have too great a sail area up to safely maneuver in the current wind conditions.
- over-reaching
- Holding a course too long while tacking.
- 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 o' nine tails, while bending, often tied down, over the barrel of a gun, known as kissing the gunner's daughter.
- overbear
- To sail downwind directly at another ship, stealing the wind from its sails.
- overboard
- Off or outside a vessel. If something or someone falls, jumps, or is thrown off of a vessel into the water, the object or person is said to have gone overboard. See man overboard.
- overfalls
- Dangerously steep and breaking seas due to opposing currents and wind in a shallow area, or strong currents over a shallow rocky bottom.
- overhead
- The ceiling of any enclosed space below decks in a vessel, essentially the bottom of the deck above.
- overhaul
- Hauling the buntline ropes over the sails to prevent them from chafing.
- overtaking sea
- Seas approaching a vessel from between 15° to port or starboard of astern at a speed greater than that of the vessel.[18]
- overwhelmed
- Capsized or foundered.
- owner
- Traditional Royal Navy term for the captain, a survival from the days when privately owned ships were often hired for naval service.
- ox-eye
- A cloud or other weather phenomenon that may be indicative of an upcoming storm.