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A  [ Alpha ] - [meaning]

• Aback - Condition of sail when the wind pressure is on the leeward or forward side, with sails backed or trimmed to windward (wind on the wrong side of the sails) Also known as "backwinded"
• Abaft - Behind or aft of; on the after side of; towards the stern relative to some other object or position.
• Abaft the beam - Any direction between the beam and the stern, more behind a vessel than in front of it. Behind a perpendicular line extending out from the middle of the boat
• Abeam - At right angles to the the fore and aft line of the boat, or beside, the boat; on the beam; also Abreast.
• Able Bodied Seamen - A member of the deck crew who is able to perform all the duties of an experienced seamen; certificated by examination; must have three years sea service. Also called Able Seamen and A.B.
• Aboard - On or in a vessel. Close aboard is close to another ship or an obstruction
• About - Across the wind in relation to the bow. When a sailboat tacks across the wind to bring it from one side to the other, she is said to go about.
• About Ship - The order to tack the ship
• Above-Board - Above the deck, and therefore open and visible. This gave rise to the term used to denote open and fair dealing.
• Above Deck - On the deck (not over it; see ALOFT).
• Abox - To lay the head-yards abox in a square rigged sailing vessel was to lay them square to the foremast in order to heave-to.
• Abreast - Alongside of; on the beam.
• ABS - American Bureau of Shipping: A U.S. based private classification, or standards setting society for merchant ships and other marine systems.
• Abyss - That part of the ocean lying below 300 fathoms from the surface.
• Access Hole - A hole through casing, bulkhead, floor or deck to enable one to reach work or gear.
• Accommodation - A cabin fitted for the use of passengers.
• A-Cockbill, A-Cockbell - Describing an anchor when it hangs by its ring at the cathead or from the hawsehole ready for letting go.
• Addendum - Additional terms at the end of a charter party.
• Admeasurement - The confirmed or official dimensions of a ship.
• Admiral - The title of a commander of a fleet or a subdivision of it.
• Admiralty Law - The law of the sea; jurisdiction over maritime causes.
• Admiralty Sweep - A large, cautious turn made to approach a gangway or to come alongside a vessel or jetty in a boat.
• Adornings - The gingerbread woodwork on the stern of old sailing ships.
• Adrift - Floating free with the currents and tide; said of a free floating object or boat which can not move by its own power; floating at random.
• Advantage - Method of reeving a tackle in order to gain the maximum increase in power.
• Advection Fog - Can occur any time warm, moist air blows over a surface cool enough to drop it's temperature below the dew point.
• Adventure - Consignments of cargo sent abroad in a ship to be sold or bartered by the master to best advantage or when the opportunity arises.
• Aerodynamic - Having a shape that that is not adversely affected by wind flowing past it.
• Aft - At, near or towards the stern; to move aft is to move back
• After Bow Spring Line - A mooring line fixed to the bow of the boat and leading aft where it is attached to the dock. This prevents the boat from moving forward in its berth. Its opposite, the forward quarter spring line, is used to keep the boat from moving aft in its berth.
• After Hatchway - The hatchway nearest the stern.
• After-leading - Said of a line that leads from its point of attachment towards the stern of the ship.
• Aftercabin - In a ship with multiple cabins, the cabin closest to the stern.
• Aftermast - In a sailing ship carrying multiple masts, the mast set closest to the stern.
• Aftermost - The farthest aft.
• Afterpart - The part of the boat behind the beam.
• Against the Sun - Anti-clockwise circular motion. Left-handed ropes are coiled down in this way.
• Age of the Tide - The interval between full moon and change of moon and the highest high tide.
• Agency Fee - A fee charged to the ship by the ship's agent, representing payment for services while the ship was in port. Sometimes called attendance fee.
• Agent - See Ship's Port Agent
• Agonic Line - Lines on the Earths surface joining point where there is no magnetic variation.
• Aground - When the hull or keel is touching or fast to the bottom of any body of water; on or onto the shore.
• Ahead - In front of the vessel, forward; in a forward direction; opposite of astern.
• Ahoy - Seaman's call to attract attention.
• AHT (Anchor-handling tug) - Moves anchors and tow drilling vessels, lighters and similar.
• Ahull - Lying almost beam on to strong winds and being driven before them while under bare poles (without sails up). The helm is lashed so as to point the vessel into the wind, but it continually falls away because of the pressure of the wind. It is a technique for riding out storms.
• Aid to Navigation (AtoN) - Any fixed object that a navigator may use to find his position, such as permanent land or sea markers, buoys, radiobeacons, and lighthouses, and to indicate safe and unsafe waters.
• Aladdin Cleat - A cleat that attaches to the backstay over the cockpit, usually used for hanging a lantern
• Albatross - Large and long-winged seabird of the southern hemisphere capable of long flights. It was believed among seamen that albatrosses embodied the souls of dead sailors, and it was considered unlucky to kill one.
• Aldis Lamp - A handheld electric lamp with a finger operated shutter used for the sending of signals at sea.
• Alee - Away from the direction of the wind; the side away from the direction of the wind.
• All Aback - With all sails filling from the opposite side from which they are trimmed.
• All Hands - The entire crew; an order on board ship for all seamen to muster on deck immediately.
• All-Around Light - A light showing an unbroken light over an arc of the horizon of 360 degrees. An anchor or riding light is an all-round light.
• All in the Wind - When a sailing vessel is head to the wind and all of her sails are fluttering.
• Allison - The act of striking or collision of a moving vessel against a stationary object.
• Almanac (Nautical) - Annual publication of astronomical data for the use of navigators.
• Aloft - Above the deck, usually overhead on the mast or in the rigging.
• Alongside - Close beside a ship, wharf or jetty.
• Aloof - Old expression meaning to "keep your luff", or sail as close to the wind as possible.
• Alow - Down or downwards; as in "Lay alow!"; opposite of Aloft.
• Altazimuth - Instrument for establishing the altitude and azimuth of stars and planets.
• Altitude - The angle a celestial body makes with the horizon.
• Amain - An old maritime expression meaning "immediately", as "let go amain" (drop the anchor at once!).
• Amas - The outboard hulls of a trimaran.
• Amidships - In or toward the part of a boat or ship midway between the bow and the stern; also midway between port and starboard sides; toward the middle of the ship or boat.
• Ammeter - An instrument for measuring electrical current in amperes.
• Amplitude - (1) In navigation, the angle between the point at which the sun rises and sets and the true east and west points of the horizon. (2) Wave height. *
• Anchor - (1) A heavy metal object, fastened to a chain or line, to hold a vessel in position, partly because of its weight, but chiefly because the designed shape digs into the bottom. (2) The act of using an anchor.
• Anchor Ball - A black ball visible in all directions, displayed in the forward part of a vessel to indicate that the vessel is anchored.
• Anchor Bed - Chocks which hold and anchor in place either in a locker or on deck.
• Anchor Bend - A type of knot used to fasten an anchor to its line.
• Anchor Buoy - A small buoy that is used to mark the position of an anchor. It is attached to the base or crown of an anchor and can be used to recover the anchor if it has to be cast adrift, or to trip it if it becomes wedged.
• Anchor is Apeak - The anchor is under the hawse .
• Anchor is Aweigh - Anchor is off the sea bottom when being heaved in .
• Anchor is Foul - Anchor cable is caught around the fluke or an object is caught around the anchor .
• Anchor Light - A white light, usually on the masthead, visible from all directions, used to indicate that a vessel is anchored.
• Anchor Warp - A hawser or line attached to an anchor.
• Anchor Watch - A member or members of the crew that keep watch and check to see whether the anchor is dragging and the the drift of the ship. This is prudent when anchored in heavy weather, or where wind direction may change dangerously.
• Anchor Windlass - A windlass is a winch-like device used to assist in the raising of the anchor.
• Anchorage - A sheltered place suitable for anchoring in relation to the wind, seas and bottom.
• Anemometer - An instrument for measuring wind speed
• Aneroid Barometer - A mechanical barometer used to measure air pressure for warnings of changing weather.
• Angle of Attack - The angle between the sail and the apparent wind or the rudder or centerline and the water flow.
• Angle of Cut - In navigation, the smaller angle at which two position lines on a chart intersect. The fix will be more reliable as the angle approaches 90°.
• Angle of Heel - The number of degrees of list a vessel has. The first indication that a vessel may need to reef is when there is too great an angle of heel.
• Annual Variation - The amount by which magnetic variation changes up or down each year in a particular area. The annual increase or decrease is printed in the compass roses on each chart and may make a significant difference over a number of years.
• Anode - see Sacrificial Anode
• Anticyclone - Area of high barometric pressure where the wind circulates clockwise in the Northern Hemisphere, and counter-clockwise in the Southern Hemisphere. These are fair weather systems with light or moderate winds.
• Antifouling Paint - A paint applied to the boat's bottom below the waterline which contains "poisons", such as copper, to inhibit the growth of marine life such as weeds or barnacles.
• Anti-Gallicans - A pair of additional backstays temporarily rigged to provide extra support to the masts of square rigged vessels when sailing downwind.
• Apeak - Said of an anchor when the cable is taut and vertical.
• Apostles - Large bollards affixed to the main deck near the bow of a square rigged vessel around which hawsers or anchor cables were belayed.
• Apparent Wind - The direction and speed of the wind as it appears to those on board, relative to the speed and direction of the boat; combination of the true wind and the wind caused by the boat's movement through the water.
• Appendage - A rudder, keel, centerboard, or skeg.
• Apron - A strengthening timber behind the lower part of the stem and above the foremost end of the keel in a wooden vessel.
• Aqualung - A device invented by Captain Jacques Cousteau in 1943 to enable a diver to operate underwater independent from an air supply from the surface.
• Arbitration - Method of settling disputes which is usually binding on parties. A clause usually in a charter party.
• Aries - The point at which the Sun , traveling in the Ecliptic , crosses the Equinoctial when going from South to North declination.
• Armstrong Patent - Slang expression to indicate that a ship was not fitted with any mechanical aids, and that all the work of the ship had to be done with the strong arms of the crew.
• Articles of Agreement - The document containing all particulars relating to the terms of agreement between the Master of the vessel and the crew. Sometimes called ship's articles or shipping articles.
• Articles of War - Disciplinary code in which maritime crimes and punishments are specified.
• Artificial Horizon - An aid to taking as astronomical sight with a sextant when the sea horizon is obscured through haze, fog, or darkness.
• Ashore - On the land or aground.
• Aspect Ratio - The relationship (ratio) between the sails height (luff length) and length along the foot. High aspect ratio means a sail that is tall and narrow, low aspect ratio is a short, squat sail. A high aspect ratio sail is very efficient in sailing close to the wind.
• A-stay - Said of an anchor cable when its line angle approximates a continuation of the fore stay line .
• Astern - Backwards, somewhere behind the vessel, towards the stern; in the direction of, or behind, the stern; opposite of ahead.
• Astrolabe - A precursor to the sextant. An old navigational device for checking the altitude of the sun or stars.
• At Sea - In marine insurance this phrase applies to a ship which is free from its moorings and ready to sail.
• Athwart - Lying along the ship's width, at right angles to the vessels fore-and-aft line (centerline). Same as abeam.
• Athwartship - A member or dimension running from port to starboard.
• Athwartships - From one side of a ship to the other.
• Atoll - A horseshoe-shaped or circular reef of coral surrounding a lagoon.
• A-trip - (1) Said of an anchor immediately when it is broken out of the ground. (2) In square-rigged ships topsails are a-trip when they are fully hoisted and ready for sheeting.
• Auster - Old Latin name for the south wind.
• Autopilot - Electro-mechanical steering device; an instrument designed to control automatically a vessel's steering gear so that she follows a pre-determined track through the water.
• Auxiliary - (1) A second method of propelling a vessel. On a sailboat this would be the engine. (2) Machinery fitted in steam and motor vessels which is not part of the main propelling machinery. (3) a support group, e.g., Coast Guard Auxiliary
• Avast - A command to stop or cease immediately what one is doing.
• Awash - Water washing over; the situation of an object when almost submerged.
• Aweigh - To raise an anchor off the bottom; the position of anchor as it is raised clear of the bottom.
• Awning - A sail or canvas set like a canopy to give shade from the sun .
• Aye - Yes. "Aye aye sir" is a reply on board ship on receipt of an order.
• Azimuth - The bearing of a celestial body from an observer's position.

B  [ Bravo ] - [meaning]

• Baboon Watch -  The unfortunate man who was assigned to remain on deck to watch over the ship's safety while the ship was in harbor, and the rest of the crew were off duty.
• Baby Stay - Secondary forestay supporting the leading edge of the mast and used to flatten the mainsail in building winds.
• Back - The wind shifts in a counterclockwise direction in the northern hemisphere and clockwise in the southern hemisphere (opposite of VEER); the wind is said to back when it changes contrary to its normal pattern.
• Back Splice - [image ] - A splice formed when a crown knot is made in the end of a piece of line and the ends are woven three times or more into the standing part of the line to keep it from unraveling.
• Backing A Sail - To push a sail out so that the wind fills the opposite side, thus slowing the boat down.
• Backing and Filling - Alternatively letting the sails draw, then spilling wind so as to keep a vessel more or less in one place until space is available, marking time.
• Backspring - A spring line from the stern of a boat to mid ships to stop forward movement
• Backstaff - A navigation instrument used to measure the apparent height of a landmark whose actual height is known, such as the top of a lighthouse. From this information, the ship's distance from that landmark can be calculated.
• Backstay - Standing or running (adjustable) wire rigging that supports the mast from the stern; a wire mast support leading aft to the deck or another mast
• Backwind - Wind that is deflected from it's normal course by the sails
• Backwinded - When the wind pushes on the wrong side of the sail, causing it to be pushed away from the wind. If the lines holding the sail in place are not released, the boat could become hard to control and heel excessively.
• Backwinding A Sail - To hold the mainsail or jib off to the side to cause the wind to blow onto the backside of the sail, used to slow a boat
• Baggywrinkle - Tassels of unraveled line, yarns, etc. which are lashed around chafe spots such as spreaders to prevent chafe on sails.
• Bail - To remove water from the boat by hand, bucket, pump etc.
• Bailers - Openings in the bottom or transom of a boat to drain water when sailing.
• Balance - The degree to which all the forces on a boat are symmetrical so the vessel sails with just a slight weather helm.
• Balance Frames - Those frames of a ship's hull which are equal in area, one forward and one aft of the ship's center of gravity.
• Bald-Headed - Sailing term used to indicate a sailing vessel underway with no headsails set.
• Bale - A metal ring on a boom, pole or mast where blocks or shackles may be attached.
• Ballast - Weight at the bottom or the lower portion of the boat to give her stability and/or to provide  satisfactory fore and aft trim.. Ballast can be place inside the hull of the boat or externally in a keel. Heavy substances can be loaded by a vessel to improve stability, trimming, sea-keeping and to increase the immersion at the propeller. Sea water ballast is commonly loaded in most vessels in ballast tanks, positioned in compartments right at the bottom and in some cases on the sides, called wing tanks. On a tanker, ballast is seawater that is taken into the cargo tanks to submerge the vessel to a proper trim.
• Ballast Tanks - Tanks carried in various parts of a ship for water ballast, for stability and to make the ship seaworthy.
• Balloon Jib - A reaching headsail that has a big draft and is usually light-weight 
• Bar - A region of shallow water usually made of sand or mud, usually running parallel to the shore. Bars are caused by wave and current action, and may not be shown on a chart.
• Bar Shot - Iron in a "dumbbell" shape shot into enemy rigging to cut lines and sails. *
• Bar Taut - Said of a rope when it is under such tension that it is practically rigid.
• Barber Hauler - A sail control used to change the athwartships lead of the jib sheet by pulling the sheet toward the centerline of the boat.
• Bare Boat Charter - A charter in which the bare ship is chartered without crew; the charterer, for a stipulated sum taking over the vessel for a stated period of time, with a minimum of restrictions; the charterer appoints the master and the crew and pays all running expenses.
• Bare Poles - Condition of a sailing ship when all sails have been taken down in a severe storm, very often a hazardous undertaking if there is a high sea running.
• Barge - (1) A cargo carrying vessel, usually without an engine, towed or pushed by a tug. Small barges for carrying cargo between ship and shore are known as lighters. (2) Also a term in sail racing - a boat which forces its way illegally between another contestant and the starting line is said to be barging.
• Barnacle - A small shellfish which sticks to the bottoms of ships.
• Barograph - An instrument used to keep a record of atmospheric pressure, such as on a paper drum.
• Barometer - An instrument that measures atmospheric pressure in inches or millibars of mercury
• Barometric Pressure - Atmospheric pressure as measured by a barometer.
• Barque (Also Bark) - A sailing ship with three to five masts, all of them square-rigged except the after mast, which is fore-and-aft rigged.
• Barquentine - Sailing vessel with three or more masts. Square rigged on foremast, fore and aft rigged on all others.
• Barratry - Any wrongful act knowingly done by the master or crew of a vessel to the detriment of the owner of either ship or cargo; and which was done without knowledge or consent of owner or owners.
• Bathyscaphe - A small free-moving submersible designed for exploring the ocean depths.
• Batten - A thin, flexible wooden or plastic strip inserted into a pocket (batten pockets) on the back part (leech) of a sail to stiffen it and assist in keeping its form.
• Batten Down - Secure hatches and loose objects both within the hull and on deck in preparation for approaching bad weather.
• Batten Pockets - Pockets in a sail where battens can be placed to stiffen the sail.
• Battle Honors - The names of battles or individual ship actions in which a warship has taken part, usually displayed in a prominent place on a ship as a source of pride in her name. Known as Battle Stars in the U.S. Navy.
• Bay - An indentation of the coastline between two headlands.
• Beachcomber - Originally a seaman who, not wanting to work, preferred to exist by hanging around ports and harbors and living on the charity of others. Now more generally describing any loafer around the waterfront who prefers not to work.
• Beacon - A lighted or unlighted fixed (non-floating) aid to navigation that serves as a signal or indication for guidance or warning. (Lights and daybeacons both constitute "beacons.")
• Beak - Name given to the metal point or ram fixed on the bows of old war galleys and used to pierce the hulls, and thus sink or disable enemy ships.
• Beam - (1) The transverse measurement of a boat at its widest point. Also called breadth. (2) One of the transverse members of a ship's frames on which the decks are laid.
• Beam Ends - Vessel said to be "on her beam ends" when she is lying over so much that her deck beams are nearly vertical.
• Beam Reach - A point of sail where the boat is sailing at a right angle to the wind (wind coming from abeam). A beam reach is usually the fastest point of sail. A beam reach is a point of sail between a broad reach and a close reach.
• Beam Sea - A situation in which waves strike a boat from the side, causing it to roll unpleasantly.
• Beam Wind - One which blows across a boat's side
• Beamy - Wide, a wide boat is a beamy boat
• Bear, to - The direction of an object from the observer's position.
• Bear Away, Bear Off - To turn the boat away from the wind. Also, Fall Off. The opposite of heading up.
• Bear Down - To approach something from upwind
• Bearing - (1) A compass direction, in compass points or degrees, from one point to another. Relative bearing is the direction relative to the heading of the boat with the bow 0 degrees and the stern 180 degrees. True bearing is the direction from the ship relating to true north with north being 0 degrees and south 180 degrees. (2) Also, a device for supporting a rotating shaft with minimum friction, which may take the form of a metal sleeve (a bushing), a set of ball bearings (a roller ball), or a set of pins around a shaft (a needle bearing).
• Beat / Beating - To sail towards the direction from which the wind blows by making a series of tacks. A point of sail also known as sailing close hauled.
• Beaufort Scale - A number system used to describe wind forces and sea conditions from 0 for a flat calm to 12 for a hurricane
• Becalm - The act of blanketing a ship by cutting off the wind, either by the proximity of the shore or by another ship. A ship motionless by the absence of wind is said to be becalmed.
• Becket - A loop or a small eye in the end of a rope or a block.
• Bee - A ring or hoop of metal.
• Bee Blocks - Wooden swells on each side of the after end of a boom, having sheaves through which to lead the leech reefing pendants.
• Bees of the Bowsprit - Pieces of hard wood bolted to the outer end of a bowsprit through which are rove the foretopmast stays before they are brought in to the bows and secured.
• Before the Mast - Said of a man who goes to sea as a rating compared with officers, and lives forward. Forward of a mast.
• Before the Wind - Sailing with the wind from astern, in the same direction toward which the wind is blowing
• Belay - (1) To make a line secure to a pin, cleat, bollard, bitt, etc. (2) Command to stop or cease action, e.g. "Belay the last order".
• Belaying Pin - Iron or wood pin fitted into racks, around which lines can be belayed or secured.
• Bell - Traditionally a ship's bell is made of brass and has her name engraved on it. It is used for striking the bells which mark the passage of time (see Bells) and is also used as a fog signal as an audible warning of a ship's position.
• Bell Buoy - A navigational buoy on which is mounted a bell with clappers hung inside  a metal cage, which is rung by the motion of the sea. It serves as a warning of shoal waters.
• Bell Rope - A short piece of line spliced into the end of the clapper by which the bell is struck. Traditionally it is finished off with a double wall knot crowned in its end.
• Bells - The strokes on the ship's bell to mark the passage of time. The passage of time in each watch is marked by the bell every half-hour.

Number of Bells	Hour (am or pm)
1	12:30	04:30	08:30
2	01:00	05:00	09:00
3	01:30	05:30	09:30
4	02:00	06:00	10:00
5	02:30	06:30	10:30
6	03:00	07:00	11:00
7	03:30	07:30	11:30
8	04:00	08:00	12:00

C  [ Charlie ] - [meaning]

• Cabin - A room or living compartment for passengers or crew.
• Cabin Sole - The floor or bottom surface of the enclosed space under the deck of a boat
• Cable - (1) A strong rope or chain for pulling or securing anything, usually a ship's anchor. (2) A nautical measurement of distance, a tenth of a nautical mile, 100 fathoms, or approximately 200 yards
• Cable Ship - A specially constructed ship for the laying and repairing of telegraph and telephone cables across channels, seas, lakes, and oceans.
• Caboose - Old term for the galley of a vessel situated normally on the deck and not between decks.
• Cabotage - The carriage of goods or passengers for remuneration taken on at one point and discharged at another point within the territory of the same country.
• Call Sign - A group of letters and numbers used for identification during radio transmission.
• Calm - Little or no wind and flat seas
• Calving - Breaking away of a mass of ice from a glacier or iceberg.
• Cam Cleat - A mechanical cleat used to hold a line automatically. It uses two spring loaded cams that come together to clamp their teeth on the line, which is place between them.
• Camber - The curvature of an object such as a sail, keel or deck. Usually used when referring to an objects aerodynamic or hydrodynamic properties. The weather decks of ships are rounded up or arched in an athwartship direction for the purpose of draining any water that may fall on them to the sides of the ship where it can be led overboard through scuppers; the camber is the crown or arch of a weather deck.
• Camel - Hollow vessel of iron, steel or wood, that is filled with water and sunk under a vessel. When water is pumped out, the buoyancy of the camel lifts the ship. Very valuable aid to salvage operations.
• Can or Can Buoy - A cylindrical navigation buoy painted green and having an odd number used in the United States as a navigational aid. At night they may have a green light.
• Canal - A manmade waterway used to connect bodies of water that do not connect naturally. Canals use locks to raise and lower boats when connecting bodies of water that have different water levels.
• Canoe Stern - A pointed stern, such as those on a canoe.
• Cant - (1) A term signifying an inclination of an object from a perpendicular; to turn anything so that it does not stand perpendicularly or square to an object. (2) Those timbers in a ship near the bow or stern which are sharply angled from the keel. (3) The operation of turning a ship's head one way or another.
• Cant Frames - Angled frames in the extreme forward or aft ends of a ship which form the sharp ends of the vessel's hull.
• Canvas - Tightly woven cloth used for sails, awnings, covers, dodgers and biminis; slang for sails.
• Cap - A piece of trim, usually wood, used to cover and often decorate a portion of the boat, i.e., caprail.
• Capsize - To turn a boat over
• Capstan - A revolving cylindrical device used for heaving in lines or anchors - A vertical, spool-shaped rotating drum around which cable, hawser or chain is wound for hoisting anchors, sails and other heavy weights. A capstan rotates around a vertical axis, as opposed to a windlass, which revolves around a horizontal axis.
• Captain - The person who is in charge of a vessel and legally responsible for it and its occupants.
• Car - A sliding fitting that attaches to a track allowing for the adjustment of blocks or other devices attached to the car.
• Caravel - Small trading vessel also used for exploration. Three-masted, being square-rigged on the two forward masts, and having a lateen rigged mizzen mast. Christopher Colmbus' small squadron, the Santa Maria, Pinta, and Nina, were all Caravels, as were Magellan's ships in his famous circumnavigation.
• Cardinal Points - The compass points of North, East, South and West. Intercardinal or half-cardinal points are Southeast, Southwest, Northwest and Northeast
• Careen - To list a vessel so that a large part of her bottom is above water. This is done to remove weed and marine growth, to examine the bottom, to repair it and to put on preservative or anti-fouling.
• Careenage - A suitable beach, being steep and sandy, where ships could be careened for cleaning or repair.
• Cargo - Ship supplies.
• Cargo Handling - The act of loading and discharging a cargo ship.
• Cargo Hatch - An opening in a ship's deck for the loading and discharging of any kind of cargo.
• Carline or Carling - Timbers used to support the deck planking of a wooden ship; also for supporting hatches.
• Carlins - Structural pieces running fore and aft between the beams.
• Carrack - Old three-masted trading vessel which was square-rigged on the fore and main masts, and lateen rigged on the mizzen mast. Similar to the Caravel, but larger and more robust.
• Carrick Bend - [image] - A knot used to tie two lines together.
• Carriers - Owners or operators of vessels providing transportation to shippers. The term is also used to refer to the vessels.
• Carry On - To continue sailing under the same canvas despite the worsening of the wind.
• Cast Adrift - To abandon a ship at sea; to place people in a ship's boat or raft and leave them.
• Cast Off - To let go of a line; to leave a dock or a mooring; to untie or loose a rope or line.
• Castaway - A shipwrecked sailor as compared with one who has been marooned or deliberately put ashore.
• Cat's Skin - Light, warm wind on surface of sea.
• Catamaran - A multihull with two hulls separated by a deck or crossbeams from which a trampoline is suspended; abbreviated "cat."
• Catboat - A small boat with the mast stepped far forward, carrying a single sail
• Cathead - On older sailing ships, a heavy piece of curved timber projecting from the bow for the purpose of holding anchors in position for letting go or for securing them after weighing.
• Catching Up Rope - Light rope secured to a buoy to hold vessel while stronger moorings are attached.
• Catenary - The curve (sag) of a rope, cable or chain hung between two points such as the anchor rode or towing line; the deeper the curve, the more catenary.
• Catharpings - In square-rigged vessels, short lines at the lower end of the futtock shrouds used to bring in the shrouds tighter to give room to brace the yards at a sharper angle when sailing close hauled.
• Cat-O'-Nine-Tails - Similar to a whip, an instrument of punishment where seamen were flogged on their bare backs.
• Catspaw - (1) A ruffle on the water indicating a breath of wind during a calm (2) A twisting hitch made in the bight of a rope to form two eyes, through which the hook of a tackle is passed for hoisting purposes. [image]
• Catug - Short for Catamaran Tug. A rigid catamaran tug connected to a barge. When joined together, they form and look like a single hull of a ship.
• Catwalk - On a ship, a raised bridge running fore and aft from the midship, and also called "walkway". It affords safe passage over the pipelines and other deck obstructions.
• Caulking/Calking - Forcing material into the seams of the planks in a boat's deck or sides to make them watertight; the material itself. Oakum was once the material used for this purpose, and was then sealed with hot pitch to prevent it from rotting. Today there are polymers used for sealing all kinds of fittings.
• Cavitation - Loss of effective propeller thrust caused by the blades cutting across the column of water sucked along by the propeller instead of working in it. Can also lead to heavy vibration of the vessel.
• Celestial Navigation - To calculate your position using time, the position of celestial bodies, and mathematical tables. Position is determined by measuring the apparent altitude of one of these objects above the horizon using a sextant and recording the times of these sightings with an accurate clock. That information is then used with tables in the Nautical Almanac to determine one's position.
• Celestial Sphere - An imaginary sphere surrounding the globe that contains the sun, moon, stars and planets.
• Center of Buoyancy - A point through which all buoyant forces on an immersed hull are assumed to act.
• Center of Effort (CE) - Point at which all of the force of the wind can be thought to concentrate; the point in the sail plan that is the balance point for all the aerodynamic forces
• Center of Lateral Resistance (CLR) - Center point of all underwater area of the hull where the hull's lateral resistance can be said to be centered.
• Centerboard - A board that can be raised and lowered by pivoting in a watertight box called the trunk or well to increase the draft and lateral area of the hull, preventing the boat from sliding sideways. Unlike a daggerboard, which lifts vertically, a centerboard pivots around a pin, usually located in the forward top corner, and swings up and aft.
• Centerboard Trunk - Watertight housing for the centerboard.
• Centerline - The imaginary line running from bow to stern along the middle of the boat.
• Certificate - A legal paper or license of a boat or its captain.
• Certificate of Registry - A document specifying the nation of registry of the vessel.
• Chafe - Abrasion, wear or damage to a line caused by rubbing against another object
• Chafing Gear - Canvas, cloth, leather, tubing, rubber or other material placed around a line or cable to protect it from wear and abrasion
• Chain Locker - The compartment, near and below the hawse holes at the bow, for stowing the anchor chains; a compartment in the lower part of a ship for stowing an anchor chain.
• Chain Pipe - A pipe of large diameter, through which the chains pass into the chain lockers.
• Chain Plate - A metal plate, strap, or rod bolted to the hull structure to which the lower ends of shrouds and stays are attached
• Chandler - A person who deals in the selling of provisions, dried stores, supplies, equipment, etc.
• Chandlery - A marine hardware store.
• Channel - A navigable route on a waterway, usually marked by buoys. Channels are deep enough for ships or boats to navigate without running aground.
• Channel Fever - Seaman's name for the excitement on board as the ship approachs her destination, giving the crew some liberty ashore.
• Chanty or Shanty - Shanties are the work songs that were used on the square-rigged ships of the Age of Sail. Their rhythms coordinated the efforts of many sailors hauling on lines.
• Characteristic - The distinguishing qualities of a navigational light, including its color and whether it is fixed or flashing (and the flashing sequence).
• Charley Noble - Galley smokestack or chimney.
• Chart - A representation on a plane surface of the spherical surface of the earth. The equivalent of a map for use by navigators.
• Chart Datum - The water level used to record data on a chart. Usually the average low tide water level. It is the level below which depths on a chart are measured, and above which keights of a tide are expressed.
• Chart Table - A table designated as the area in the boat where the navigator will study charts and plot courses.
• Charter - The renting of a boat
• Chearly - An old expression meaning heartily or quickly.
• Check - To ease away slowly, as in a line, sheet, or falls of a tackle.
• Checking - Slacking a rope smartly, carefully and in small amounts.
• Cheek Block - A block with one end permanently attached to a surface.
• Cheeks - (1) The two sides of a block. (2) Pieces of timber attached to the mast below the masthead to support the trestle trees.
• Cheese Down - To coil down the tail of a line on deck to present a neat appearance.
• Chief Engineer - The senior engineer officer responsible for the satisfactory working and upkeep of the main and auxiliary machinery and boiler plant on board ship.
• Chief Mate - The officer in the deck department next in rank to the master; second in command of a ship. He is next to the master, most especially in the navigation and as far as the deck department is concerned. The chief mate assumes the position of the Master in his absence.
• Chinch - The operation of pressing oakum into a seam as a temporary measure until the seam can be properly caulked.
• Chine - The angle of intersection between the topsides and the bottom of a boat. In a hard-chined boat this angle is pronounced.
• Chock - (1) A deck fitting to guide an anchor, mooring, towing or docking line. Usually smooth shaped to reduce chafe. (2) A wedge or block to keep an object from moving.
• Chock-a-Block - When a line is pulled as tight as is can go, as when two blocks are pulled together so that no further movement is possible (also known as "Two blocked").
• Choke the Luff - To temporarily stop all movement of a line through a block by placing the hauling part across the sheave of the block. This jams the sheave and holds it tight, and a pull on the hauling part will release it.
• Chop - Small, steep disorderly waves at rapid intervals.
• Chord - An imaginary line drawn between the luff and leech of a sail. The chord depth is an imaginary line drawn to the deepest part of the sail from the chord. The ratio of chord depth to chord length represents the sail's draft - a high ratio indicates a full sail; a low ratio, a flat sail.
• Chow - Food.
• Chute - An opening in the deck near the bow from which the spinnaker is hoisted. Spinnakers are also often referred to as chutes.
• Ciguatera - A severe type of food poisoning caused by eating contaminated fish
• Circumnavigate - To sail around the world
• Circumnavigation - A voyage around the world.
• Clap On - To clap on is to temporarily add something to an existing part.
• Class - General category into which boats of the same or similar design are grouped for racing.
• Classification Society - Worldwide experienced and reputable societies which undertake to arrange inspections and advise on the hull and machinery of a ship. A private organization that supervises vessels during their construction and afterward, in respect to their seaworthiness, and the placing of vessels in grades or "classes" according to the society's rules for each particular type.
• Claw Off - Beat to windward to avoid being driven onto a lee shore.
• Claw Ring - A "C" shaped fitting which can be slipped over the boom, for example, when the sail has been roller reefed to allow the boom vang to be reattached.
• Clean - Referring to the lines of a vessel's hull when they give a a fine and unobstructed run from bow to stern so that she moves through the water smoothly.
• Clear - (1) Free, not entangled (2) To finalize all formalities in a Customs House.
• Clear for Running - A sheet or halyard coiled so that it will run out quickly without becoming tangled.
• Clear the Decks - Remove unnecessary things from the decks usually in preparation for oncoming bad weather.
• Cleat - A fitting of wood or metal, secured to the deck, mast, or spar, with two horns around which ropes are made fast. The classic cleat to which lines are belayed is approximately anvil-shaped; verb - to belay.
• Clevis Pin - A large pin that secures one fitting to another.
• Clew - The lower aft corner of a fore and aft sail, both lower corners of a spinnaker, and the lower corners of a square sail
• Clew Outhaul - The tackle used to adjust the clew in and out on the boom.
• Clinometer - Instrument showing the angle of heel of a vessel, usually a weighted pointer resembling a pendulum, that swings along an arc that is marked in degrees. *
• Clipper - A sharp-bowed sailing vessel of the mid-19th century, having tall masts and sharp lines; built for great speed; the generic name used to describe types of fast sailing ships.
• Clock Calm - Absolutely calm weather with a perfectly smooth sea.
• Close Aboard - Close alongside; very near; in close proximity to.
• Close Hauled - A point of sail where the boat is sailing as close to the wind (as directly into the wind) as possible; sails are pulled in tight, enabling the boat to point as high as possible to the direction the wind is coming from; Also, "beating" and "on-the-wind".
• Close Reach - Sailing with the wind coming from the direction forward of abeam. A close reach is the point of sail between a beam reach and close hauled.
• Closest Point of Approach (CPA) - The nearest another vessel will come to yours when both are under way, usually expressed in distance and relative bearing.*
• Clothing - Various pieces of rigging which hold a bowsprit in position.
• Clove Hitch - [image] - Two half hitches around a spar or post. Easy way to make a line temporarily fast to a piling or post. The clove hitch can jam under heavy tension, making it difficult to untie. Worse, is its tendency to untie itself when subjected to repeated strain and release, such as a boat rocking in waves. You can add one or two half hitches on the standing line for a more secure attachment.
• Club - A boom on a jib or staysail.
• Coach Roof - The cabin roof, raised above the deck to provide headroom in the cabin. Also trunk.
• Coachwhipping - Decorative ropework with an even number of strands to form a herring-bone pattern.
• Coaming - A low vertical lip or raised section around the edge of a cockpit, hatch, etc. to prevent water on deck from running below.
• Coast Pilots - Books covering information about coastal navigation, including navigational aids, courses, distances, anchorages and harbors.
• Coastal Navigation - Navigating near the coast, allowing one to find one's position by use of landmarks and other references.
• Coastwise - Domestic shipping routes along a single coast.
• Cocked Hat - The small triangular space found at the intersection of lines of position on a chart when a ship's position is determined by taking three bearings.
• Cockpit - The location from which the boat is steered, usually in the middle or at the stern of the boat.
• Cockpit Sole - Floor of the cockpit.
• Cockswain - The steersman of a boat, in direct charge of the crew if any. Pronounced "Cock-sun."*
• Coffee Grinder - A large and powerful sheet winch
• Cofferdam - A void or empty space separating two or more compartments for the purpose of insulation, or to prevent the liquid contents of one compartment from entering another in case of a leak.
• COG - Course Over Ground
• Coil - To lay a line down in circular turns, known as fakes, or to arrange in loops so it can be stowed. Line is sold by the coil, which contain 200 fathoms
• Cold Front - Used in meteorology to describe a mass of cold air moving toward a mass of warm air. Strong winds and rain typically accompany a cold front.
• Cold Molding - A method of bending a material into an appropriate shape without heating or steaming the material first to soften it.
• Colimation - Correct alignment of the optical parts of an instrument.
• Collier - Vessel used for transporting coal.
• Collision Avoidance System - Electronic system commonly used to prevent collisions in inland navigable waterways.
• Collision Bulkhead - A watertight bulkhead at the forepeak extending to main deck. This bulkhead prevents the entire ship from being flooded in case of a collision.
• Collision Mat - A large square of heavy canvas fitted with lines to allow it to be drawn under the hull of a ship where it is damaged. The pressure of the seawater holds it tight against the ship and greatly reduces the inflow of water.
• Colors - National flag or insignia flown by a ship at sea.
• COLREGS - Convention on International Regulations for Preventing Collisions at Sea; Rules of the Road. Internationally accepted rules by which vessels at sea must keep clear of each other.
• Comb the Cat - When flogging a seaman, to run the fingers through the Cat-O'-Nine-Tails after each stroke to separate the strands in preparation for the next stroke.
• Combi - Combination passenger/cargo vessel.
• Combined Ships - Ships which can carry both liquid and dry bulk cargoes.
• Come/Coming About - Bringing the boat from one tack to the other when sailing into the wind, so that the sail is flown in the opposite side by turning through the eye of the wind; Tack
• Come Home - An anchor is said to come home when its flukes are not holding in the ground and it drags.
• Commander - The naval rank next below that of Captain.
• Commission - (1) The documents by which naval officers hold their status as accredited officers in the navy they serve. (2) To place a vessel into active service. Decommission is to remove such a vessel from activity.
• Commodore - (1) An intermediate rank between Captain and Rear Admiral, often held by a senior captain when given extra responsibility. (2) The leader of a yacht club.
• Companion Way - The area leading down from the deck to the cabin, usually with steps (ladder)
• Company - The whole crew of a ship.
• Compartments - The spaces between the transverse bulkheads of a ship.
• Compass - Navigation instrument, either magnetic, containing a magnetized card indicating the direction to magnetic north (showing magnetic north) or gyro (showing true north).
• Compass Card - A card labeling the 360° of the circle and the named directions such as north, south, east and west. Part of a compass, the circular card is graduated in degrees. It is attached to the compass needles and conforms with the magnet meridian-referenced direction system inscribed with direction. The vessel turns, not the card.
• Compass Course - The direction of a ship's heading as read on a compass. The compass course has added the magnetic deviation and the magnetic variation to the true course.
• Compass Error - The amount the compass is deflected from the true direction by variation (magnetic) and deviation (metallic influences) together
• Compass Rose - A circle on a chart, showing all 360°, indicating the direction of geographic north and sometimes also magnetic north.
• Complement - The number of officers and crew employed upon a vessel for its safe navigation and operation.
• Composite Construction - An object made with more than one type of material.
• Compression Post - A vertical post, supporting the coach roof or deck, between a deck-stepped mast and (usually) the keel.
• Con - Station, usually on the bridge, from which a ship is controlled; the act of so controlling.
• Container Ship - A ship constructed in such a way that she can easily stack containers near and on top of each other as well as on deck. The hull is divided into cells that are easily accessible through large hatches, and more containers can be loaded on deck atop the closed hatches.
• Continental Shelf - A region of relatively shallow water surrounding a land mass where the depth increases gradually before it plunges into the deeps of the ocean.
• Contline - The spiral grooves between the strands of rope after it has been laid up.
• Contraband - Goods which have been prohibited from entering a belligerent state by the declaration of a blockade.
• Convoy - One or more merchant ships sailing in company to the same destination under the protection of naval ships.
• Co-ordinates - The definition of the exact position on the surface of the globe in relation to two lines, latitude and longitude, which intersect at right angles.
• Copper Sheathing - Thin sheets of copper applied to the hull of a wooden ship below the waterline to prevent the toredo worm eating the planks, and also to limit the growth of weed, barnacles or other marine life.
• Cordage - Any rope or line.
• Corinthian - A 19th century term for a yachtsman who sails his own yacht without the help of a professional skipper.
• Corsair - A private ship operating under license from a government against the merchant shipping of an enemy.
• Cotter Pin - A small double-pronged bendable pin used to secure a clevis pin or to keep turnbuckles from unwinding.
• Counter - The overhang of the stern aft of the stern post. At the stern of the boat, that portion of the hull emerging from below the water, and extending to the transom.
• Counter Current - That part of the water which is diverted from the main stream of a current and as a result flows in the opposite direction.
• Course - (1) The prescribed compass direction in which a vessel is being steered (2) The lowest yard on a mast (square-rigged vessels). (3) The large square sail that hangs from that yard (4) The sequence of marks rounded in a race
• Course Protractor - An instrument with a movable arm to plot a course on a chart
• Courtesy Flag - A smaller version of the flag of the country being visited. It is flown from the starboard spreader.
• Cove - (1) A small coastal inlet generally protected from the worst of the prevailing winds. (2) A thin, hollowed line cut along a yacht's sheer below deck level and traditionally gilded.
• Cover - In sailboat racing, to have a controlling position over competitors by staying between them and the next mark or buoy - a tactical maneuver in which the lead boat stays between the trailing boat and the wind or the next mark.
• Cow-Hitch - Any bend or hitch which slips as a result of being improperly tied; an improvised knot which is not a recognized maritime knot as used at sea.
• Cowls - Scoop like devices used to direct air into and ventilate a boat.
• Coxswain, Cockswain - The helmsman.
• CQD - The original distress call made by a ship requiring assistance, giving way to SOS.  It stood for CQ, the signal for all stations (still used by Amateur Radio Operators, or Hams), and D for distress; it also meant "Come Quickly, Danger" 
• CQR Anchor - An anchor that is designed to bury itself into the ground by use of its plow shape. Also called a plow anchor.
• Crabbing - Going sideways due to a current's set.
• Crack On - To carry sail to the full limit of strength of masts, yards, and tackles.
• Cradle - A frame that supports a boat when she's hauled out of the water onto shore.
• Craft - Vessel or vessels of practically any size or type.
• Crank - Said of a vessel with little stability, whether due to design or to stowage of cargo.
• Creep - To search for a sunken object by towing a grapnel along bottom.
• Crest - The top of a wave.
• Crew - Personnel, excluding the Master, who serve on board a vessel (also excludes the passengers on passenger ships). In some cases a differentiation between officers and ratings is made; but officers are "crew" in a legal sense.
• Crew List - List prepared by the master of a ship showing the full names, nationality, passport or discharge book number, rank and age of every officer and crew member engaged on board that ship. This serves as one of the essential ship's documents which is always requested to be presented and handed over to the customs and immigration authorities when they board the vessel on arrival.
• Cribbing - Timbers used to support bottom of ship while it is under construction.
• Crimp - Person who decoys a seaman from his ship and gains money by robbing and, or, forcing him on board another vessel in want of men.
• Cringle - A large reinforced eye in the leech and clew of a sail that allows a line to fasten to it; e.g., the reef cringle and clew cringle.
• Cross Bearing - Two or more bearings are noted on the chart in order to determine the ship's position at the intersection of the two
• Cross Bracing - Iron or steel straps fastened diagonally across a ship's frames to make a rigid framework.
• Cross-Jack Yard - The lower yard on a mizzen mast of a square-rigged ship.
• Cross Sea - A sea running in a direction contrary to the wind, which can be confused and dangerous.
• Crossing the Line - A ceremony performed on board ships when passengers or crew are crossing the equator for the first time during a voyage.
• Crosstrees - Small horizontal spars extending athwartships from one or more places along the mast. The shrouds cross the end of these "spreaders", enabling the shrouds to better support the mast.
• Crown - A knot formed by taking the strands of the end of a line and tucking them over and under each other to prevent them from unraveling. 
• Crow's Nest - A platform and protective coaming setting high up on a mast, to accommodate the look-out aloft while the ship is at sea.
• Cruise - Voyage made in varying directions. To sail in various directions for pleasure, in search, or for exercise.
• Cuddy - A small sheltered cabin on a boat.
• Culage - Laying up of a vessel, in a dock, for repairs.
• Cunningham - A line used to control the tension along a sail's luff in order to maintain proper sail shape.
• Current - Horizontal movement of the water caused by tidal change, wind, river movement, or circular currents caused by the motion of the earth.
• Customary Dispatch - Usual and accustomed speed.
• Customs - Government officials responsible for regulating goods, services and supplies into a country.
• Customs Manifest - Document listing all personal goods of crew members.
• Cut - The shape or design of a sail.
• Cut of His Jib - The recognition of a person by his recognizable characteristics (originally, the shape of the nose)
• Cut Splice - Two lines spliced together to form an eye.
• Cutlass - A short, curved sword associated with naval hand-to-hand combat. *
• Cutlass Bearing - The bearing surrounding the propeller shaft where it exits the hull.
• Cutter - A single masted sailboat similar to a sloop except sails are arranged so that many combinations of areas may be obtained. A sail plan with two headsails, a main jib and a smaller staysail set between the jib and the mast.
• Cutting His Painter - A seaman's personal "painter" is his lifeline, and if it is severed, he dies.
• Cutwater - The forward curve of the stem of a ship.

D  [ Delta ] - [meaning]

• Dacron - A synthetic polyester material.
• Daggerboard - Similar to a centerboard, except that it is raised and lowered vertically in a trunk rather than pivoted. Like a keel, daggerboards are used to reduce leeway by preventing a sailboat being pushed sideways by the wind.
• Danforth Anchor - A brand of lightweight anchor. It has pivoting flukes that dig into the ground as tension is placed on the anchor.
• Davit(s) - A small crane that projects over the side of the boat to raise or lower objects (such as smaller boats) from or to the water.
• Davy Jones - Nautical slang for the spirit of the sea, usually in the form of a sea devil. Davy Jones's Locker is the bottom of the sea, the final resting place of sunken ships, articles lost or thrown overboard, and of men buried at sea.
• Daybeacon - A fixed navigation aid structure, visible during the day, used in shallow waters upon which is placed one or more daymarks.
• Daymark - A signboard attached to a daybeacon to convey navigational information presenting one of several standard shapes (square, triangle, rectangle) and colors (red, green, orange, yellow, or black).  Daymarks usually have reflective material indicating the shape.
• Daysailor - A small boat intended to be used only for short sails or racing.
• Dayshape - Black diamond, ball, and cone shapes hoisted on vessels during the day to indicate restricted movement, ability, or type. For example three balls means aground.
• Dead Ahead - A position directly in front of the vessel.
• Dead Astern - A position directly aft or behind the vessel.
• Dead on End - Said of wind when exactly ahead; and of another vessel when her fore and aft line coincides with observer's line of sight.
• Dead Horse - Seaman's term for the period of work on board ship for which he has been paid in advance when signing on.
• Dead Marine - An empty wine bottle after its contents have been drunk.
• Dead Reckoning - The process of plotting a theoretical position or future position based on advancing from a known position using speed, time, and course, without aid of objects on land, of sights, etc. Term comes from deduced reckoning, abbreviated first to "ded reckoning".
• Deadeyes - Circular blocks in the shrouds or stays to adjust tension.
• Deadfreight - Space booked by shipper or charterer on a vessel but not used
• Deadhead - (1) A floating log. (2) A useless member of the crew, a person skylarking.*
• Deadlight - Fixed ports that do not open which are placed in the deck or cabin to admit light.
• Deadrise - The measurement of the angle between the bottom of a boat and its widest beam. A vessel with a 0º deadrise has a flat bottom, high numbers indicate deep V shaped hulls.
• Deadweight - A common measure of ship carrying capacity. The number of tons (2240 lbs.) of cargo, stores and bunkers that a vessel can transport. It is the difference between the number of tons of water a vessel displaces "light" and the number of tons it displaces "when submerged to the 'deep load line'." A vessel's cargo capacity is less than its total deadweight tonnage. The difference in weight between a vessel when it is fully loaded and when it is empty (in general transportation terms, the net) measured by the water it displaces. This is the most common, and useful, measurement for shipping as it measures cargo capacity.
• Deadwood - Heavy longitudinal timbers fastened over the keelson. The timbers of the bow and stern are fastened to the deadwood.
• Deck - A permanent covering over a compartment, hull or any part of a ship serving as a floor.
• Deck Beam - A beam which supports a deck.
• Deck Gang - The officers and seamen comprising the deck department aboard ship. Also called deck crew, deck department, or just deck.
• Deck Girders - Continuous longitudinals fastened under the deck.
• Deck House - A small house erected upon the deck of a ship for any purpose. A low building or superstructure, such as a cabin, constructed on the top deck of a ship.
• Deck Log - Also called Captain's Log. A full nautical record of a ship's voyage, written up at the end of each watch by the deck officer on watch. The principal entries are: courses steered, distance run, compass variations, sea and weather conditions, ship's position, principal headlands passed, names of lookouts, and any unusual happenings such as fire, collision, etc.
• Deck Officer - As distinguished from engineer officer, refers to all officers who assist the master in navigating the vessel when at sea, and supervise the handling of cargo when in port.
• Deck Plate - A metal plate fitting on the deck that can be opened to take on fuel or water
• Deck Prism - A prism inserted into the deck which provides light down below.
• Deck Stepped - A mast that is stepped (placed) on the deck of a boat rather than through the boat and keel stepped. The mast of a deck stepped boat is usually easier to raise and lower and are usually intended for lighter conditions than keel stepped boats.
• Deckhand - Seaman who works on the deck of a ship and remains in the wheelhouse attending to the orders of the duty officers during navigation and maneuvering. He also comes under the direct orders of the bosun.
• Deckhead - The underside of the deck, viewed from below the ceiling.
• Declination - The angular distance North or South of the equator, measured from the center of the earth. It thus corresponds to latitude on the earths surface.
• Deep V - Refers to the shape of a boat's (usually power boat) hull. A deep V hull is usually good at cutting through rough waves at high speeds.
• Deep Waterline - The line to which a vessel is submerged with a full car