Trademarked type of polyester used in many sails.
To moderate motion.
A brand name for an anchor. Often used to indicate any lightweight anchor.
A bearing or course that marks the limit of safe navigation. To go the wrong side of it is to place the boat at risk.
Five or more quick blasts on a horn or whistle to alert nearby boats to potential danger.
dangerous semicircle, dangerous quadrant
The most risky part of a gale or storm, it is the right front section as the storm advances (the left front section in the Southern Hemisphere).
A small crane on deck, used to hoist a dinghy, anchor, or other object.
daybeacon, beacon, daymark
A stake driven into the bottom at the edge of a channel and displaying a placard (daymark) with identifying numbers and colors. It takes the place of a buoy as an aid to navigation in very shallow water.
To go sailing for a few hours. A daysailer is a boat without a cabin (though she may have a cuddy), used for short sails and racing.
A signal hung during the day to indicate the vessel's type or activity, for example a black ball when the boat is anchored.
Exact, direct, complete. An object that is dead ahead is directly ahead. To sail dead (square) before the wind is to have the wind directly on the stern. To power dead (square) into the waves is to go straight into them. A dead muzzler is a strong wind from dead ahead. In a dead calm there is no wind. Dead reckoning (D.R.), see navigate and position.
To secure an end of a line to a stationary object.
A mostly submerged log, sometimes used as a mooring buoy.
dead in the water
A port or window that cannot be opened.
dead reckoning, D.R.
See navigate and position.
The angle of the boat's bottom to the horizontal. A flat bottom has 0 degrees of deadrise. A deep-V powerboat hull has about 25 degrees.
The part of a keel that does not contain ballast.
The lid on a boat on which the crew walks and sits. A decked boat (deck boat) has a deck, unlike an open boat. The foredeck is forward of the cockpit in a powerboat, of the mast in a sailboat. A deck beam is a length of wood, fiberglass, or wood supporting the deck. The side decks are on both sides. The afterdeck is near the stern. A deck box is a locker on deck. Deck gear consists of cleats, winches, blocks, and other equipment used on deck. A deck shower is a freshwater shower installed on deck or in the cockpit. A deck-house is a small cabin on deck. Deck shoes have special soles (nonskid soles) that grip a wet, pitching deck. A deck filler is an opening in the deck through which a fuel or water tank is filled. A deck plate is a small removable hatch in the deck. Decksweeper, see low.
See fiberglass and laminated.
A direct passage to get the boat to a location where she will be met by her owner. Compare with cruise.
Leaving port at the beginning of a voyage. The vessel takes her departure when she clears land. At the point of departure her crew notes the location, the time, the course, and the mileage.
To decrease the wind's effect on a sailboat by flattening or reefing a sail, or by changing down to a smaller sail.
depth, water depth
The distance from the water's surface to the water's bottom.
depthsounder, echo sounder, sounder, Fathometer, depthfinder
An electronic device that indicates the depth of water. A recording depthsounder produces a record of depth readings over time.
A notch in a boat's gear shift that, when engaged, keeps the engine in gear.
Movement of a compass card (measured in degrees west or east) caused by metal or magnetism in the boat. A deviation card displays the amount of deviation at different headings.
A diesel engine, diesel fuel.
See Global Positioning System.
An eating area in a boat. A convertible dinette can be made into a berth.
A small, light boat. Compare with pram and tender.
Wind directions indicate the direction of the wind is blowing from, for example a northwester is a wind from the northwest. All other directions indicate direction toward, for example to steer a course of northwest is to head toward the northwest (or into a northwest wind). See wind.
Wind affected by another object.
Suddenly without a mast.
Technically the amount and weight of water that a hull pushes aside, but generally a boat's weight. It is measured in pounds or in cubic feet, determined by dividing the displacement in pounds by 64. Light displacement describes a boat that is relatively lightweight for her length, heavy displacement describes a relatively heavy boat, and moderate displacement is in the middle. The displacement/length ratio (D/L ratio) is a number that indicates a sailboat's displacement relative to her size. The larger the number, the heavier she is. See sail area/displacement ratio.
displacement hull (boat)
An especially heavy, full-ended hull or boat. A semidisplacement hull (semidisplacement boat) is somewhat lighter.
A boat's distance from a charted object. In the distance-off navigation technique, the boat's position is estimated by gauging the distance off from land or a lighthouse's light. That distance is charted as a circle of position. See position.
See ocean race.
The distance a boat has covered in a known period of time.
A flare or other visual signal indicating an emergency.
See abandon ship.
A small bag used to stow and carry a knife, light line, tools, and other boatswain's gear.
divided rig, split rig
Calipers (two short metal legs joined at a hinge) used to measure distances on a chart.
Technically, the water in which a boat sits when she is tied to a float, pier, or wharf. However, the term usually is used to mean the float, pier, or wharf itself. To dock is to pull in to or alongside a dock. Dockage is the fee charged for docking, which may be supervised by a dockmaster. A docking line (dockline) is a line used to tie a boat to another object. See breast line, springline. A dock cart is a wheelbarrow or wagon used to carry gear down a pier or wharf to the water.
A boat registered with the federal government rather than with a state.
A spray shield over and around a hatch.
A shelter forward of a cockpit or over a hatch.
A calm area in the middle of an ocean between the trade winds.
A small wave.
A trailer for dinghies, used on launching ramps and in boatyards and not intended to be pulled behind cars.
Pilings tied together.
A flat-bottomed, double-ended rowing boat originally used as a fishing boat on the Grand Banks.
To do twice. To double a peninsula is to sail around it. To double up a line is to rig a backup line. In a double-bottomed boat, there is a watertight compartment between the bottom and the cockpit sole.
A boat with a pointed stern. See transom.
With a crew of two.
double-headsail rig, double-head rig, cutter rig
Having two jibs set simultaneously on two stays. The outer sail (the jib) is set on the headstay; the inner one (the staysail, forestaysail) is set on the forestay.
To lower or roll up a sail or awning.
See head off.
The coast of Maine, especially north and east of Mt. Desert Island.
Water pouring below through a hatch or other opening on deck.
A line or tackle that pulls down a sail at its tack or holds down a spinnaker pole (also foreguy).
Away from the direction from which the wind is blowing. Opposite of upwind.
Dead reckoning, dead-reckoning plot. See navigate and position.
draft, dr., draw
1) The boat's extreme depth, from her waterline to her lowest point. A boat has 3 feet of draft or draws 3 feet; alternatively, her draft is 3 feet. 2) The fullness or camber of a sail. See chord.
1) Dragging anchor, see anchor. 2) To drag for something on the water's bottom is to scrape the bottom with a grapnel hook or net. 3) Concerning sails and appendages, drag is resistance to wind or water caused by the object's shape, surface friction, and the process of generating forward force (lift) from air and water flow. Eddies around the leech of a sail or the stern of a boat indicate the presence of drag. Compare with lift and stall.
1) See draft. 2) To design a boat.
To display flags from bow to stern and aloft in honor of a holiday or an event. A form of flag etiquette.
1) The current's velocity. Compare with set. 2) To not make any speed by power, sail, or oar but rather be pushed by the waves and current. Drifting conditions are almost nonexistent winds. A drifting match is a race held in drifting conditions. A drifting jib or drifter (also windseeker) is a light, small sail set in very light wind.
1) To increase speed. When a sailboat drives off she heads off and speeds up. To drive over another boat means to go by her on her windward side. To drive (push) a boat hard is to push her to near her and her crew's limits. Driving power is a boat's ability to be pushed hard. 2) Driveshaft, the transmission for a boat engine. She V-drive. 3) Steer. The automotive terms drive and driver have recently come to be used by racing sailors and powerboaters to mean "steer" and "steerer" (helmsman).
A device used to ride out heavy weather and storms. It is a small parachute or other object towed astern. See storm. Compare with sea anchor.
A relative word when used in a boat, it generally means that all the water comes from the sea. A dry nor'easter kicks up plenty of spray but provides no rain.
Rot in wood.
dry store, dry sail
To keep a boat out of the water when she is not in use.
Waterproof one-piece clothing that keeps water out and maintains body heat. Compare with survival suit and wet suit.
Two steering wheels, one on either side. They allow the steerer to sit far to one side or the other for better visibility forward.
1) To duck another boat or duck astern of her is to steer behind her, passing astern. 2) To duck behind a point of land or breakwater is to go from open water to shelter, where there is protection form wind and waves.
A channel for air leading to a ventilator.
DWL, designed waterline
Describes a wind that is fading or a sea that is growing flatter.