At Sea Glossary - H
halyard
A line used to hoist a sail or spar. The tightness of the halyard can affect sail shape.
harbor
An anchorage protected from storms either naturally or by manmade barriers.
harbormaster
The individual who is in charge of a harbor.
hatch
A sliding or hinged opening in the deck, providing access to thecabin or space below.
haul
Pulling on a line.
head
1) The front of a vessel.
2) The upper corner or edge of a sail.
3) The top or front of a part.
4) The toilet and toilet room in a vessel.
heading
The actual course of the vessel at any given time.
headsail
Any sail forward of the mast, such as a jib.
head seas
Waves coming from the front of the vessel.
headstay
The most forward forestay. The line from the bow or bowsprit to the top of the mast. This keeps the mast from falling toward the rear of the boat. The headstay is the farthest forward of all thestays on the boat.
heave
To throw or pull strongly on a line.
heaving line
A light line used to be thrown ashore, from which a larger rope can then be pulled.
heaving to
Arranging the sails in such a manner as to slow or stop the forward motion of the boat, such as when in heavy seas.
heavy seas
When the water has large waves or breakers in stormy conditions.
heavy weather
Stormy conditions, including rough, high seas and strong winds. Probably uncomfortable or dangerous.
heel, heeling
When a boat tilts away from the wind, caused by wind blowing on the sails and pulling the top of the mast over. Some heel is normal when under sail.
helm
The wheel or tiller of a boat.
helmsman
The person who is steering the boat.
high tide
The point of a tide when the water is the highest. The opposite oflow tide.
hitch
A knot used to attach a line to a cleat or other object.
holding ground
The type of bottom that the anchor is set in.
holding tank
A storage tank where sewage is stored until it can be removed to a treatment facility.
horseshoe buoy
A floatation device shaped like a U and thrown to people in the water in emergencies.
hull
The main structural body of the boat, not including the deck, keelor mast. The part that keeps the water out of the boat.
hull speed
The theoretical speed a boat can travel without planing, based on the shape of its hull. This speed is about 1.34 times the square root of the length of a boat at its waterline. Since most monohullsailboats cannot exceed their hull speed, longer boats are faster.
hurricane
An intense tropical weather system with a well-defined circulation and maximum sustained winds of 74 miles per hour (64 knots or higher in the North Atlantic Ocean, the Northeast Pacific Ocean (east of the International Date Line) or the South Pacific Ocean (east of 160° east longitude). In other parts of the world, they are known as typhoons, tropical cyclones and severe tropical cyclones.
hydrodynamic
A shape designed to move efficiently through the water.
hydrofoil
A boat that has foils under its hull onto which it rises to plane across the water surface at high speed.
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