Glossary of Nautical Terms

Safe Harbour: A harbour which provides safety from bad weather
Safe Haven: A safe harbour, including natural harbours, which provide safety from bad weather or attack.
Sagging: When the trough of a wave is amidships, causing the hull to deflect so the ends of the keel are higher than the middle. The opposite of hogging.
Sail: 1. A piece of fabric attached to a vessel and arranged such that it causes the wind to drive the vessel along. It may be attached to the vessel via a combination of mast, spars, and ropes.; 2. The power harnessed by a sail or sails to propel a vessel.; 3. To use sail power to propel a vessel.; 4. A trip in a boat or ship, especially a sailboat or sailing ship.; 5. In American usage, a sail is a tower-like structure on the dorsal (topside) surface of submarines constructed since the mid-20th century which houses periscopes, access trunks for the bridge, etc.; called a fin in European and British Commonwealth countries. It differs from the conning tower of earlier submarines, which was similar in appearance to a sail or fin, but housed instruments and controls from which the periscopes were used to direct the submarine and launch torpedo attacks, functions not performed in a modern sail (or fin).
Sailing Skiff: see 'Skiff'.
Sail loft: A large open space used by sailmakers to spread out sails.
Sailmaker: A craftsman who makes and repairs sails, working either on shore in a sail loft or aboard a large, ocean-going sailing ship.
Sail-plan: A set of drawings showing various sail combinations recommended for use in various situations.
Saltie: Great Lakes term for a vessel that sails the oceans.
Salty dog: Slang for a sailor, especially for a seaman in the navy.
Sampan: A relatively flat bottomed Chinese wooden boat from 3.5 to 4.5 m long; some with a small shelter and may be used as permanent habitation on inland waters; generally used in coastal areas or rivers and as traditional fishing boats. It is unusual for a sampan to sail far from land as they do not have the means to survive rough weather.
Sampson post: A strong vertical post used to support a ship's windlass and the heel of a ship's bowsprit.
Scandalize: To reduce the area and efficiency of a sail by expedient means (slacking the peak and tricing up the tack) without properly reefing, thus slowing boat speed. Also used in the past as a sign of mourning.
Scantlings: Dimensions of ships structural members, e.g., frame, beam, girder, etc.
Schooner: A type of sailing vessel characterized by the use of fore-and-aft sails on two or more masts with the forward mast being no taller than the rear masts, first used by the Dutch in the 16th or 17th century.
Scow: 1. A method of preparing an anchor for tripping by attaching an anchor cable to the crown and fixing to the ring by a light seizing (also known as becue). The seizing can be broken if the anchor becomes fouled.; 2. A type of clinker dinghy, characteristically beamy and slow.
Screw: 1. Propeller.; 2. Propeller-driven (e.g., screw frigate, screw sloop).
Scud: A name given by sailors to the lowest clouds, which are mostly observed in squally weather.
Scudding: A term applied to a vessel when carried furiously along by a tempest.
Scull: 1. An oar used for sculling.; 2. A boat propelled by sculling, generally for recreation or racing.
Sculling: A method of using oars to propel watercraft in which the oar or oars touch the water on both the port and starboard sides of the craft, or over the stern. On sailboats with transom-mounted rudders, forward propulsion can be made by a balanced side to side movement of the tiller, a form of sculling.
Scuppers: Originally a series of pipes fitted through the ships side from inside the thicker deck waterway to the topside planking to drain water overboard, larger quantities drained through freeing ports, which were openings in the bulwarks.
Scuttle: A small opening, or lid thereof, in a ship's deck or hull.
Scuttlebutt: 1. A barrel with a hole in used to hold water that sailors would drink from. By extension (in modern naval usage), a shipboard drinking fountain or water cooler.; 2. Slang for gossip.
Scuttling: Making a hole in the hull of a vessel or opening seacocks, especially in order to sink a vessel deliberately.
Sea anchor: A stabilizer deployed in the water for heaving to in heavy weather. It acts as a brake and keeps the hull in line with the wind and perpendicular to waves. Often in the form of a large bag made of heavy canvas. Also see drogue.
Seaboots: High waterproof boots for use at sea. In leisure sailing, known as sailing wellies.
Sea chest: A watertight box built against the hull of the ship communicating with the sea through a grillage, to which valves and piping are attached to allow water in for ballast, engine cooling, and firefighting purposes. Also a wooden box used to store a sailor’s effects.
Seacock: a valve in the hull of a boat.
Seaman: Generic term for sailor, or (part of) a low naval rank
Sea trial: The testing phase of a boat, ship, or submarine, usually the final step in her construction, conducted to measure a vessel’s performance and general seaworthiness before her owners take delivery of her.
Seaworthy: Certified for, and capable of, safely sailing at sea.
Self-unloader: Great Lakes slang term for a vessel with a conveyor or some other method of unloading the cargo without shoreside equipment.
Sennet whip: A summary punitive implement
Sextant: Navigational instrument used to measure a ship's latitude.
Shaft alley: Section of a ship that houses the propulsion shaft, running from the engine room to the stuffing box.
Shakedown cruise: A cruise performed before a ship enters service or after major changes such as a crew change, repair, or overhaul during which the performance of the ship and her crew are tested under working conditions.
Shakes: Pieces of barrels or casks broken down to save space. They are worth very little, leading to the phrase "no great shakes".
Shanghaied: Condition of a crewman involuntarily impressed into service on a ship.
Sheer: The upward curve of a vessel's longitudinal lines as viewed from the side.
Sheer plan: In shipbuilding, a diagram showing an elevation of the ship's sheer viewed from the broadside.
Sheet: A rope used to control the setting of a sail in relation to the direction of the wind.
Shell (in the United Kingdom also fine boat): An extremely narrow, and often disproportionately long, rowing boat outfitted with long oars, outriggers to hold the oarlocks away from the boat, and sliding seats, specifically designed for racing or exercise.
Shift colors: Changing the flag and pennant display when a moored vessel becomes underweigh, and vice versa. A highly coordinated display that ships take pride in; the desired effect is that of one set of flags vanishing while another set flashes out at precisely the same time. Also, slang for changing out of one's Navy uniform into civilian clothes to go ashore. (The U.S. Navy's newsletter for retired personnel is nicknamed Shift Colors from this reason.)
Shift tides: Sighting the positions of the sun and moon using a sextant and using a nautical almanac to determine the location and phase of the moon and calculating the relative effect of the tides on the navigation of the ship.
Ship: Strictly, a three-masted vessel square-rigged on all three masts, or on three masts of a vessel with more than three. Hence a ship-rigged barque would be a four master, square-rigged on fore, main and mizzen, with spanker and gaff topsail only on the Jigger-mast. Generally now used refers to most medium or large vessels outfitted with smaller boats. As a consequence of this, submarines may be larger than small ships, but are called boats because they do not carry boats of their own.
Ship-of-the-line: A type of sailing warship constructed from the 1600s through the mid-1800s to serve as part of the line of battle; the largest and most powerful warships of the era.
Ship rig
Ship-rigged ship: See #Full rigged ship.
Ship sloop: A type of sloop-of-war introduced in the 1740s which had three square-rigged masts (in contrast to the brig sloop introduced in the 1770s, which had two masts).
Ship's bell: Striking the ship's bell is the traditional method of marking time and regulating the crew's watches.
Ship's biscuit: See hard tack.
Ship's company: The crew of a ship.
Ship's complement: The number of persons in a ship's crew, including officers.
Shipyard: A facility where ships or boats are built and repaired. Routinely used as a synonym for dockyard, although dockyard sometimes is associated more closely with a facility used for maintenance and basing activities, while shipyard sometimes is associated more closely with a facility used in construction.
Shoal: Shallow water that is a hazard to navigation.
Shoal draught: Shallow draught, making the vessel capable of sailing in unusually shallow water.
Shore leave: Free time given to officers and crew of a naval vessel when they are off duty and allowed to disembark and spend time on land. See also liberty.
Short stay: The relative slackness of an anchor chain; this term means somewhat slack, but not vertical nor fully extended.
Shot across the bow: A shot fired close to and in front of a moving vessel to warn her to stop, often for boarding.
Shroud: A rope or cable serving to hold a mast up from side to side.
Shrouds: Standing rigging running from a mast to the sides of a ships to support the mast sideways.
Sick bay: The compartment reserved for medical purposes.
Sidewheel: 1. A side-mounted paddle wheel used for propulsion by a paddle steamer.; 2. Propelled by a sidewheel (e.g., "sidewheel steamer").
Siren: A sound signal which uses electricity or compressed air to actuate either a disc or a cup shaped rotor.
Skeg: A downward or sternward projection from the keel in front of the rudder. Protects the rudder from damage, and in bilge keelers may provide one "leg" of a tripod on which the boat stands when the tide is out.
Skiff: A small boat, traditionally a coastal or river craft, for leisure or fishing, with a single person or small crew. Sailing skiffs have developed into high performance competitive classes.
Skipper: The captain of a ship.
Skysail: A sail set very high, above the royals. Only carried by a few ships.
Skyscraper: A small, triangular sail, above the skysail. Used in light winds on a few ships.
Sloop: A small to mid-sized sailboat larger than a dinghy, with one mast bearing a main sail and head sail and located farther forward than the mast of a cutter.
Sloop-of-war: 1. In the 18th and 19th centuries, a small sailing warship carrying 18 or fewer guns with a single continuous gundeck.; 2. In the 18th and 19th centuries, any sailing warship bearing fewer than 20 guns.; 3. In the 19th-century United States Navy, the term used for the type of sailing warship known in other navies as a corvette.; 4. In the early and mid-20th century, a small ocean-going warship not intended for fleet deployments, used instead for convoy escort, gunboat duties, etc.
Slop chest: A ship's store of merchandise, such as clothing, tobacco, etc., maintained aboard merchant ships for sale to the crew.
Slush: Greasy substance obtained by boiling or scraping the fat from empty salted meat storage barrels, or the floating fat residue after boiling the crew's meal. In the Royal Navy the perquisite of the cook who could sell it or exchange it (usually for alcohol) with other members of the crew. Used for greasing parts of the running rigging of the ship and therefore valuable to the master and bosun.
Slush fund: The money obtained by the cook selling slush ashore. Used for the benefit of the crew (or the cook).
Smack: A traditional fishing boat used off the coast of England and the Atlantic coast of America for most of the 19th century and in small numbers up to the mid-20th century. Originally a cutter-rigged sailing boat, after about 1865 lengthened and given a ketch rig. Some had a topsail on the mizzen mast, others a bowsprit carrying a jib.
Small bower (anchor): The smaller of two anchors carried in the bow.
Snow: A form of brig where the gaff spanker or driver is rigged on a "snow mast" a lighter spar supported in chocks close behind the main-mast.
Son of a gun: The space between the guns was used as a semi-private place for trysts with prostitutes and wives, which sometimes led to birth of children with disputed parentage. Another claim is that the origin the term resulted from firing a ship's guns to hasten a difficult birth.
Sonar: A method of using sound pulses to detect, range and sometime image underwater targets and obstacles, or the bed of the sea. Also see echo sounding and ASDIC.
Sou'wester: 1. A storm from the south west.; 2. A type of waterproof hat with a wide brim over the neck, worn in storms.
Sounding: Measuring the depth of the water. Traditionally done by swinging the lead, now commonly by echo sounding.
Spanker: A fore-and-aft or gaff-rigged sail on the aft-most mast of a square-rigged vessel and the main fore-and-aft sail (spanker sail) on the aft-most mast of a (partially) fore-and-aft rigged vessel such as a schooner, a barquentine, and a barque.
Spanker-mast: The aft-most mast of a fore-and-aft or gaff-rigged vessel such as schooners, barquentines, and barques. A full-rigged ship has a spanker sail but not a spanker-mast (see Jigger-mast).
Spar: A wooden, in later years also iron or steel pole used to support various pieces of rigging and sails. The big five-masted full-rigged tall ship Preussen (German spelling: Preußen) had crossed 30 steel yards, but only one wooden spar—the little gaff of its spanker sail.
Spar torpedo: A weapon consisting of a bomb placed at the end of a long spar and attached to a boat.
Speaking tube: see communication tube.
SOG: Speed over ground, speed of the vessel relative to the Earth (and as shown by a GPS). Referenced on many fishing forums.
Spider band
Spider hoop: An iron band around the base of a mast which holds a set of iron belaying pins.
Spindrift: Finely divided water swept from crest of waves by strong winds.
Spinnaker: A large sail flown in front of the vessel while heading downwind.
Spinnaker pole: A spar used to help control a spinnaker or other headsail.
Spotting top: A platform on a mast used to aid in gun laying.
Spring: A line used parallel to that of the length of a craft, to prevent fore-aft motion of a boat, when moored or docked.
Splice: To join lines (ropes, cables etc.) by unravelling their ends and intertwining them to form a continuous line. To form an eye or a knot by splicing.
Splice the mainbrace: A euphemism, it is an order given aboard naval vessels to issue the crew with a drink, traditionally grog. The phrase splice the mainbrace is used idiomatically meaning to go ashore on liberty, intending to go out for an evening of drinking.
Spreader: A spar on a sailboat used to deflect the shrouds to allow them to better support the mast.
Spurling pipe: A pipe that connects to the chain locker, from which the anchor chain emerges onto the deck at the bow of a ship.
Square meal: A sufficient quantity of food. Meals on board ship were served to the crew on a square wooden plate in harbor or at sea in good weather. Food in the Royal Navy was invariably better or at least in greater quantity than that available to the average landsman. However, while square wooden plates were indeed used on board ship, there is no established link between them and this particular term. The OED gives the earliest reference from the U.S. in the mid 19th century.
Squared away: Yards held rigidly perpendicular to their masts and parallel to the deck. This was rarely the best trim of the yards for efficiency but made a pretty sight for inspections and in harbor. The term is applied to situations and to people figuratively to mean that all difficulties have been resolved or that the person is performing well and is mentally and physically prepared.
Squat effect: The phenomenon by which a vessel moving quickly through shallow water creates an area of lowered pressure under its keel that reduces the ship's buoyancy, particularly at the bow. The reduced buoyancy causes the ship to "squat" lower in the water than would ordinarily be expected, and thus its effective draught is increased.
S.S. (or SS): Prefix for "Steam Ship," used before a ship's name.
Stack (also funnel): See #Funnel.
Stanchion: vertical post near a deck's edge that supports life-lines. A timber fitted in between the frame heads on a wooden hull or a bracket on a steel vessel, approx one meter high, to support the bulwark plank or plating and the rail.
Standing rigging: Rigging which is used to support masts and spars, and is not normally manipulated during normal operations. Cf. running rigging.
Stand-on (vessel): A vessel directed to keep her course and speed where two vessels are approaching one another so as to involve a risk of collision.
Starboard: The right side of the boat. Towards the right-hand side of a vessel facing forward. Denoted with a green light at night. Derived from the old steering oar or steerboard which preceded the invention of the rudder.
Starboard tack: When sailing with the wind coming from the starboard side of the vessel. Has right of way over boats on port tack.
Starter: A rope used as a punitive device. See teazer, togey.
Stateroom: 1. A superior cabin for a vessel's officer.; 2. In American usage, also a private passenger cabin in a vessel
Stay: Rigging running fore (forestay) and aft (backstay) from a mast to the hull.
Staysail: A sail whose luff is attached to a forestay.
Steamer: A vessel equipped with steam propulsion. Also steamboat or steamship.
Steerage: 1. The effect of the helm on a vessel; the act of steering a vessel.; 2. 19th- and early 20th-century term for the section of a passenger ship that provided inexpensive accomodation with no individual cabins.
Steerageway: The minimum speed at which a vessel will answer the helm, below which she cannot be steered.
Steering flat: In a vessel, the compartment containing the steering gear.
Steering oar or steering board: A long, flat board or oar that went from the stern to well underwater, used to steer vessels before the invention of the rudder. Traditionally on the starboard side of a ship (the "steering board" side).
Steeve: A spar or derrick with a block at one end, used for stowing cargo.
Stem: The extension of keel at the forward end of a ship.
Stern: The rear part of a ship, technically defined as the area built up over the sternpost, extending upwards from the counter to the taffrail.
Stern chaser: See chase gun.
Stern tube: 1. The tube under the hull to bear the tailshaft for propulsion (usually at stern).; 2. A torpedo tube mounted in the stern of a submarine.
Sterndrive: A propeller drive system similar to the lower part of an outboard motor extending below the hull of a larger power boat or yacht, but driven by an engine mounted within the hull. Unlike a fixed propeller (but like an outboard), the boat may be steered by twisting the drive. Also see inboard motor and outboard motor.
Sternwalk: An external walkway or gallery for the use of officers installed on the stern chiefly of British warships until the early 20th century.
Sternway: The reverse movement of a boat or watercraft through the water.
Strike: 1. To haul down or lower (a flag, mast, etc.).; 2. To surrender the vessel to the enemy, from strike the colors.; 3. To remove a naval vessel's name from a country's naval register (after which the vessel is considered stricken).
Strike the colors: To surrender the vessel to an enemy, from the custom during the Age of Sail of lowering the vessel's ensign to indicate that she is surrendering.
Stopper knot: A knot tied in the end of a rope, usually to stop it passing through a hole; most commonly a figure-eight knot.
Stove or Stove in: (past tense of stave, often applied as present tense) to smash inward, to force a hole or break in, as in a cask, door or other (wooden) barrier.
Stow: to store, or to put away e.g. personal effects, tackle, or cargo.
Stowage: the amount of room for storing materials on board a ship.
Stowaway: A trespasser on a ship; a person aboard a ship without permission and/or without payment, and usually boards undetected, remains hidden aboard, and jumps ship just before making port or reaching a port's dock; sometimes found aboard and imprisoned in the brig until the ship makes port and the prisoner can be transferred to the police or military.
Straggler: In a convoy, a ship that is unable to maintain speed and falls behind.
Strake: One of the overlapping boards in a clinker built hull.
Stretcher: an inclined foot rest, attached to the boat, to which a rower may place and in some instances (usually in competition) attach his feet.
Studding-sails (/ˈstʌnsəl/): Long and narrow sails, used only in fine weather, on the outside of the large square sails.
Superstructure: The parts of the ship or a boat, including sailboats, fishing boats, passenger ships, and submarines, that project above her main deck. This does not usually include its masts or any armament turrets.
Surge: A vessel's transient motion in a fore and aft direction.
Sway: 1. A vessel's lateral motion from side to side.; 2. (v) To hoist: "Sway up my dunnage".
Sweep: A long oar used to steer an unpowered lighter.
Swigging: To take up the last bit of slack on a line such as a halyard, anchor line or dockline by taking a single turn round a cleat and alternately heaving on the rope above and below the cleat while keeping the tension on the tail.
Swinging the compass: Measuring the accuracy in a ship's magnetic compass so its readings can be adjusted—often by turning the ship and taking bearings on reference points.
Swinging the lamp: Telling sea stories. Referring to lamps slung from the deckhead which swing while at sea. Often used to indicate that the story teller is exaggerating.
Swinging the lead: 1. Measuring the depth of water beneath a ship using a lead-weighted sounding line. Regarded as a relatively easy job, thus:; 2. Feigning illness etc to avoid a hard job.

Read more about this topic: Glossary Of Nautical Terms

Glossary of Nautical Terms - S