Backstay: A wire support for the mast, usually running from the stern to the head of the mast.
Bale A fitting on the end of a spar, such as the boom, to which a line may be led.
Ballast Weight, usually metal, placed low in a boat to provide stability.
Barber Hauler, A line attached to the jib or jib sheet, used to adjust the angle of sheeting by pulling the sheet toward the centerline of the boat.
Battens Flexible strips of wood or plastic, most commonly used in the mainsail to support the aft portion, or roach, so that it will not curl.
Bilge A rounding of the hull along the length of the boat where the bottom meets the side.
Bilgeboards Similar to centerboards, and used to prevent lee way. Bilgeboards are located on either side of the centerline at the bilges.
Binnacle A support for the compass, raising it to a convenient position.
Board boat A small boat, usually mono rig. May have a shallow cockpit well. Typically has almost no freeboard.
Bobstay Wire stay underneath the bowsprit; helps to counteract the upward pull exerted by the forestay.
Boom crutch Support for the boom, holding it up and out of the way when the boat is anchored or moored. Unlike a gallows frame, a crutch is stowed when boat is sailing.
Boom Vang A system used to hold the boom down, particularly when boat is sailing downwind, so that the mainsail area facing the wind is kept to a maximum. Frequently extends from the boom to a location near the base of the mast. Usually tackle- or lever-operated.
Boomkin (bumpkin) Short spar extending aft from the transom. Used to anchor the backstay or the sheets from the mizzen on a yawl or ketch.
Boot top A stripe near the waterline.
Bowsprit A short spar extending forward from the bow. Normally used to anchor the forestay.
Bridge deck The transverse partition between the cockpit and the cabin.
Bridle A short length of wire with a line attached at the midpoint. A bridle is used to distribute the load of the attached line. Often used as boom travelers and for spinnaker down hauls.
Bulkhead An interior partition commonly used to stiffen the hull. May be watertight.
Bullseye A round eye through which a line is led, usually in order to change the direction of pull.
Bulwark A vertical extension above the deck designed to keep water out and to assist in keeping people in.
Cap A piece of trim, usually wood, used to cover and often decorate a portion of the boat, i.e., caprail.
Centerboard A board lowered through a slot in the centerline of he hull to reduce sideways skidding or leeway. Unlike a daggerboard, which lifts vertically, a centerboard pivots around a pin, usually located in the forward top corner, and swings up and aft.
Chain plate The fitting used to attach stays to the hull. Chine A line, running along the side of the boat, where the bottom forms an angle to the side. Not found on round-bottom boats.
Clew For a triangular sail, the aftmost cornet.
Coach roof Also trunk. The cabin roof, raised above the deck to provide headroom in the cabin.
Coaming A vertical extension above the deck to prevent water from entering the cockpit. May be broadened to provide a base for winches.
Companionway The main entrance to the cabin, usually including the steps down into the cabin.
Counter At the stern of the boat, that portion of the hull emerging from below the water, and extending to the transom. Apr to be long in older designs, and short in more recent boats.
Cunningham A mainsail control device, using a line to pull down the mainsail a short distance from the luff to the tack. Flattens the sail.
Daggerboard A board dropped vertically through the hull to prevent leeway. May be completely removed for beaching or for sailing downwind.
Deadlight Either a cover clamped over a porthole to protect it in heavy weather or a fixed light set into the deck or cabin roof to provide light below.
Dodger A screen, usually fabric, erected to protect the cockpit from spray and wind.
Downhaul A line used to pull a spar, such as the spinnaker pole, or a sail, particularly the mainsail, down.
Dry sailing When boats, especially smaller racers, are kept on shore instead of being left anchored or moored, they are dry sailed. The practice prevents marine growth on the hull and the absorption of moisture into it.
Fairlead A fitting used to alter the direction of a working line, such as a bullseye, turning block, or anchor chock.
Fo'c'sle An abbreviation of forecastle. Refers to that portion of the cabin which is farthest forward. In square-riggers often used as quarters for the crew.
Foot For a triangular sail, the bottom edge.
Forepeak The compartment farthest forward in the bow of the boat. Often used for anchor or sail stowage.
Forestay Wire, sometimes rod, support for the mast, running from the bowsprit or foredeck to a point at or near the top of the mast.
Foretriangle The triangle formed by the forestay, mast, and fore deck.
Fractional rig A design in which the forestay does not go to the very top of the mast, but instead to a point 3/4~ 7s, etc., of the way up the mast.
Freeboard: The distance between the deck and the waterline. Most often it will vary along the length of the boat.
Garboard Used in conjunction with strake. Refers to the planks, or strakes, on either side of and adjacent to the keel.
Gollywobbler A full, quadrilateral sail used in light air on schooners. It is flown high, between the fore and main mast, and is also known as a fisherman's staysail.
Gooseneck The fitting that connects the boom to the mast.
Gunter rig Similar to a gaff rig, except that the spar forming the "gaff" is hoisted to an almost vertical position, extending well above the mast.
Gunwale Most generally, the upper edge of the side of a boat.
Guy A line used to control the end of a spar. A spinnaker pole, for example, has one end attached to the mast, while the free end is moved back and forth with a guy.
Halyard Line, usually of wire, that is used to pull up or hoist a sail.
Head For a triangular sail, the top corner. Also a marine toilet. Head knocker A block with a jam cleat, located on the boom and used to control the main sheet on small boats.
Headfoil A grooved, streamline rod, often aluminum, fitted over the forestay. The primary purpose is to provide continuous support of the luff of the sail, but it may also help support the forestay.
Hiking stick An extension of the tiller that enables the helms man to sir at a distance from it.
Inspection port A watertight covering, usually small, that may be removed so the interior of the hull can be inspected or water removed.
IOR International Offshore Rating
Jiffy reefing A fast method of reefing. Lines pull down the luff and the leech of the sail, reducing its area.
Jumper stay A short stay supporting the top forward portion of the mast. The stay runs from the top of the mast forward over a short jumper strut, then down to the mast, usually at the level of the spreaders.
Keelson A structural member above and parallel to the keel. Kick-up Describes a rudder or centerboard that rotates back and up when an obstacle is encountered. Useful when a boat is to be beached.
Lapper A foresail which extends back of and overlapping the mast, such as a 110% genoa jib.
Lazarette A stowage compartment at the stern.
Lazy jack: Light lines from the topping lift to the boom, forming a cradle into which the mainsail may be lowered.
Lead refers to the direction in which a line goes. A boom yang, for example, may "lead to the cockpit."
Lee boards Pivoting boards on either side of a boat which serve the same function as a centerboard. The board to leeward is dropped, the board to windward is kept up.
Leech The aft edge of a triangular sail.
Leech line A line running through the leech of the sail, used to tighten it.
Loose-footed Describes a mainsail attached to the boom at the tack and clew, but not along the foot.
Luff The forward edge of a triangular sail. In a mainsail the luff is that portion that is closest to the mast.
Mast step Fitting or construction into which the base of the mast is placed.
Masthead rig A design in which the forestay runs to the peak of the mast.
Mechanical advantage (or purchase) A mechanical method of increasing an applied force. Disregarding the effects of friction, if a force of 100 pounds applied to a tackle is magnified to a force of 400 pounds, the purchase or mechanical advantage is said to be four to one, or 4: 1.
Mizzen A fore and aft sail flown on the mizzenmast.
MORC Midget Ocean Racing Fleet
150 percent genoa For rating purposes, the length of a line drawn perpendicular to the luff and intersecting the clew is divided by the length of the base of the Foretriangle. For instance, if the former is 30 feet and the latter 20 feet, the genoa is rated at 30/20 = 1.5, or 150 percent.
Outhaul Usually a line or tackle, an outhaul is used to pull the clew of the mainsail towards the end of the boom, thus tightening the foot of the sail.
Pedestal A vertical post in the cockpit used to elevate the steering wheel into a convenient position.
PHRF Performance Handicap Racing Fleet
Pulpit A metal framework on deck at the bow or stern. Provides a safety railing and serves as an attachment for the lifelines.
Pushpit Colloquial, a pulpit located on the stern.
Rake The fore or aft angle of the mast. Can be deliberately induced (by adjustment of the standing rigging) to flatten sails, balance steering, etc. Normally slightly aft.
Reef points: A horizontal line of light lines on a sail which may be tied to the boom, reducing the area of the sail during heavy winds.
Roach The curved portion of a sail extending past a straight line drawn between two corners. In a mainsail, the roach extends past the line of the leech between the head and the clew and is often supported by battens.
Rocker The upward curvature of the keel towards the bow and stern.
Roller reefing: Reduces the area of a sail by rolling it around a stay, the mast, or the boom. Most common on headsails.
Rub-rail: Also rubbing strake or rub strake. An applied or thickened member at the rail, running the length of the boat; serves to protect the hull when alongside a pier or another boat.
Running backstay: Also runner, or preventive backstay. A stay that supports the mast from aft, usually from the quarter rather than the stern. When the boat is sailing downwind, the runner on the leeward side of the mainsail must be released so as not to interfere with the sail.
Running rigging The adjustable portion of the rigging, used to control sails and equipment.
Sandwich construction Layered materials such as FRP-foamFRP. Usually adhesively bonded. Typically strong and light. Often used in hulls; very widely used in decks.
Scupper Drain in cockpit, Coaming, or toe-rail allowing water to drain out and overboard.
Scuttle A round window in the side or deck of a boat that may be opened to admit light and air, and closed tightly when required.
Seat locker A storage locker located under a cockpit seat.
Self-bailing cockpit A watertight cockpit with scuppers, drains, or bailers that remove water.
Self-tacking Normally applied to a sail that requires no adjustment other than sheeting when the boat is tacked.
Sheer The line of the upper deck when viewed from the side. Normal sheer curves up towards the bow and stern,
Reverse sheer curves down towards the bow and stern.
Compound sheer, curving up at the front of the boat and down at the stern, and straight sheer are uncommon.
Sheer strake The topmost planking in the sides, often thicker than other planking.
Sheets: Lines used to control the position of a sail. Shrouds Lateral supports for the mast, usually of wire or metal rod.
Skeg: For sailboats, usually refers to a structural support to which the rudder is fastened.
Slab reefing Also points reefing, and sometimes jiffy reefing. Reduces the area of the mainsail by partially lowering the sail and resecuring the new foot by tying it to the boom with points, or light lines attached to the sail.
Sole The floor of the cockpit or cabin.
Spar Poles, most often of wood, aluminum or carbon fiber, used as supports, such as the mast, boom, or spinnaker pole.
Spinnaker A large, triangular sail, most often symmetrical, flown from the mast in front of all other sails and the forestay. Used sailing downwind.
Spirit The spar that supports the peak of a spritsail. Splashboard A raised portion of the hull forward of the cockpit intended to prevent water entering.
Spreaders: Also crosstrees. Short horizontal struts extending from the mast to the sides of the boat, changing the upward angle of the shrouds.
Spritsail A four-sided fore and aft sail set on the mast, and supported by a spar from the mast diagonally to the peak of the sail.
Standing rigging Permanent rigging used to support the spars. May be adjusted during racing, in some classes.
Staysail A sail that is set on a stay, and not on a yard or a mast.
Stem The most forward structural member in the bow.
Strake: On wooden boats, a line of planking running from the bow to the stern along the hull.
Tabernacle A hinged mast step located on deck. Since it is hinged, the mast may be lowered easily.
Tack On a triangular sail, the bottom forward corner. Also, to turn the boat so that the wind exerts pressure on the opposite side of the sail.
Taffrail The rail at the stern of the boat.
Tang A fitting, often of sheet metal, used to attach standing rigging to a spar, or to the hull.
Thwart A transverse structural member in the cockpit. In small boats, often used as a seat.
Toe-rail A low rail, often slotted, along the side of the boat. Slots allow drainage and the attachment of blocks.
Topping lift A line or wire rope used to support the boom when a boat is anchored or moored.
Trampoline The fabric support that serves for searing between the hulls of a catamaran.
Transom The flat, or sometimes curved terminating structure of the hull at the stern of a boat.
Trapeze Wire gear enabling a crewmember to place all of his weight outboard of the hull, thus helping to keep the boat level.
Traveler A fitting across the boat to which sheets are led. In many boats the traveler may be adjusted from side to side so that the angle of the sheets can be changed to suit conditions.
Twing Similar to a Barber hauler, a twing adjusts the angle of sheeting.
Vang A device, usually with mechanical advantage, used to pull the boom down, flattening the sail.
Ventilator Construction designed to lead air below decks. May have a cowl, which can be angled into or away from the wind; and may be constructed with baffles, so that water is not allowed below, as in Dorade ventilator.
Warp Heavier lines (rope or wire) used for mooring, anchoring and towing. May also be used to indicate moving (warping) a boat into position by pulling on a warp.
Whisker pole A short spar, normally kept stowed, which may be used to push the clew of a jib away from the boat when the boat is running downwind.
Window A transparent portion of a jib or mainsail.
Wishbone A boom composed of two separate curved pieces, one on either side of the sail. With this rig, sails are usually self tending and loose-footed.