Nautical Glossary
courtesy of "the geek"
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alee - adv. At or to the leeward side.

apparent wind - The combination of true wind and wind caused by the motion of a vessel.

backstay - n. Part of the standing rigging, a line or cable used to reinforce the mast by connecting the top of the mast to the stern of a vessel.

beam - n. The width of of a vessel at its widest point.

beam reach - Sailing with the wind approximately 90 degress off the vessel's centerline (abeam).

beating - v. Sailing almost into the wind.

before the wind - Sailing with the wind directly behind the vessel. Also known as running.

bow - n. The front portion of a vessel.

clew - n. The aft bottom corner of a sail.

COLREGS - (The International Regulations for Preventing Collisions at Sea, 1972) Rules of the road governing vessels operating on the high seas.



foot - n. The bottom edge of a sail.


"Hard a lee!" - Traditional command given by skipper or helmsman to indicate the start of a tacking maneuver. Refers to the action of pushing the tiller to the leeward side of the vessel which initiates the process.

head - n. 1) The top corner of a sail. 2) Sometimes used to refer to the forward end of a vessel (eg. A vessel that is trimmed poorly because it has taken on water or has too much weight forward, may find itself "down by the head").

hull speed - Maximum speed a hull can attain without planing. It is generally considered to be approximately equal to the square root of the vessel's waterline length multplied by 1.34.

in irons - Used to refer to a sailboat which has lost all speed because it is headed into (or close enough to) the wind.

"Jibe ho!" - Traditional command given by skipper or helmsman to indicate the start of a jibe maneuver.

knot - A unit used to describe the speed of boat or ship that is equivalent to one nautical mile per hour.

leach - n. The aft edge of a sail.

leeward - (loo-ward) adj. The side of a vessel, island, peninsula, etc. away from the wind.

line - General term for any rope or cable that is used on a boat, particularly the standing or running rigging on board a sailboat. (Remember: There are no "ropes" on a sailboat - only "lines"!)

luff - n. The forward edge of a sail. - v. Condition of a vessel or sail where the forward edge of the sail (luff) flaps and becomes less effective usually because the sail is trimmed in too far.


nautical mile - A unit of distance equal to 6080 feet used on boats, ships, and airplanes (compare to the statute mile).


planing - A situation in which a hull is supported by the hydrodynamic forces while moving through the water in addition to displacement buoyancy.


riprap - n. Large slabs of stone used as a protective barrier at the edge of a body of water.

running - Sailing with the wind directly behind the vessel.

sheet - Line used to control the angle of a sail with respect to apparent wind.

statute mile - A unit of distance equal to 5280 feet used on land (compare to the nautical mile).

tack - n. 1) The forward bottom corner of a sail. 2) A heading with respect to wind direction maintained by a sailboat. v. A turning maneuver where the bow of the vessel passes through the wind (also refered to as "coming about").







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