
GLOSSARY OF TERMS
[a]
Aft
Referring to the "after end" or stern of the boat.
"We walked aft along the deck."
Auxiliary
An engine in a sailboat used for an additional source, not the main source.
Also used to refer to a sailboat with such an engine.
[b]
Bearing off
Steering away from the source of the wind - steering toward the
leeward side of one's course. The opposite of "heading up".
"After sailing out of Boston Harbor against a moderate easterly
wind, the boat was seen bearing off to the south and heading for
Cape Cod Canal."
Bilge
The lowest regions inside the hull of a boat. Most of the water
that enters the hull of a boat will find its way to the bilge.
Bilge pump - a pump to remove water from the bilge.
Blowing the bilge
The practice of ventilating the bilge before starting a gasoline engine.
It is accomplished with an electric fan that removes the old air and draws
in fresh air. The purpose is to avoid the presence of gasses in the bilge
that could ignite when the engine is started.
Boom
A horizontal spar, usually made of wood or aluminum, which is attached
to the foot, or bottom edge of the mainsail. The boom is attached to the
main sheet (a line) which can be adjusted to allow the mainsail to be set
close to the centerline of the boat (close hauled) or extended at a greater
angle to that center line up to 90 degrees.
Bow
The front of the boat.
In the heavy sea, waves came over the bow.
Buoy
A floating device designed to hold something up on the surface of the water.
A ring buoy is a common life saving device that can be thrown to a person in
danger of drowning. A mooring buoy holds a line from a heavy mooring on the
surface of the water where it is accessible to boats that wish to tie up to
that mooring.
[c]
Cleat
An item of marine hardware to which a line (rope) can be conveniently and
securely attached.
Close hauled
Having the sails pulled in as close as possible to the middle of the hull
of the boat, allowing the boat to sail as the closest possible angle
(usually about 45 degrees) to the direction (source) of the wind.
Coming about
The act of changing tacks in a sailboat by steering through the source of the
wind. As a result of this act the sails fill on that side of the boat which is
opposite the side they were on before coming about.
Concave
Referring to a surface which is not perfectly flat but dish-shaped as the inside of
a plate or bowl. The windward side of a full sail takes a concave shape. The opposite
of convex.
Convex
Referring to a surface which is not perfectly flat but mound-shaped as the outside of
a plate or bowl. The leeward side of a full sail takes a convex shape. The opposite
of concave.
Course
The path of an object across a surface. In boating, the path a boat is taking across
the surface of the water.
"The boat sailed a course of due West to enter Long
Island Sound."
Cockpit
An area aboard a sailboat, usually near the stern, defined by the presence of steering
and sail controls and space for the crew to tend such controls.
[d]
Downwind
Going with the wind. Referring to the direction of travel or a location which
is the same as the direction of the wind. Opposite of upwind - going against
the wind.
[e]
Ease
To allow a line under tension to be pulled out by that tension.
In the case of a sheet (line controlling the shape of the sails)
it means to let the sheet out, thereby allowing the sail to extend
further from the boat.
[f]
Forestay
A piece of rigging (usually wire rope) which supports the mast of a sailboat
by running from the formost part of the hull of a boat to a point at the top
or part way up the mast. The jib of a sailboat is often attached to this
forestay.
[g]
Groove
In sports, referring to the optimum state of balance and performance.
In sailing, the course taken with the sails properly set which allows the boat to
reach its maximum speed and best angle to the wind for prevailing conditions.
"Our boat was in the groove and we were fast approaching our final
destination."
Gybe
An act of changing a sailboat's direction with respect to the wind which causes
a sudden swing of the mainsail from one side to the other. The sailboat is headed
downwind for this maneuver and the mainsail is usually hauled in to prevent damage or
injury.
Gybe ho!
The command given by the helmsperson when the gybe is about to take place.
[h]
Hatch
An opening in the deck of a boat that allows access to compartments below deck.
A watertight lid to prevent water from entering the hull of the boat can cover a
hatch.
Heading up
The act of turning the boat toward the direction of the wind.
Opposite of "bearing off".
Heel
The sideways tip or incline of a sailboat away from horizontal which is caused
by pressure sideways on the mast, usually from the wind filling the sails. A strong
gust coming from the starboard side caused the boat to heel far to port.
Hull
The body of a sailboat to which the spars, rudder, keel and other fittings are attached.
Easy Wind's hull is white with blue stripes at the waterline and just below the deck.
Hull speed
The maximum speed that a boat can travel through the water without planing
(skimming across the surface). Hull speed is fixed by a boat's waterline length, the
longer the length, the greater the hull speed. Easy Wind's hull speed is about 7
knots.
[i]
Inboard
Located within the hull of the vessel as opposed to outboard - outside the hull.
Easy Wind has an inboard engine whereas another sailboat might be powered by
an outboard motor.
[j]
Jib
The sail which occupies the foremost position in the rig of a boat.
Jibs are triangular in shape and their forward edge is usually attached to
a stay (wire) that also supports the mast.
Jib Sheet
Two sheets control the jib, one on the starboard (right) side of the boat,
the other on the port side. While sailing, one of these sheets is always
working; the other one is slack. The sheet that is working is on the side
that the sails are set, the slack sheet is on the other side. When the boat
changes tacks and the jib is trimmed on the opposite side, the other sheet
becomes the working sheet. Each sheet starts at the aft (back) corner of the
sail (the clew of the sail) and runs to a block attached to the rail of the
boat at the very edge of the deck. After passing through the block, the
working sheet is wrapped around a winch and fastened to a cleat. When a boat
comes about the working jib sheet is released and the slack jib sheet is
trimmed.
[k]
Keel
The bottom extension of the hull of a sailboat. A keel may reach down to a
depth of eight feet or more, depending on the size of the boat. It is usually
made of a very heavy material such as lead and it provides lateral stability and
prevents the boat from slideslipping when under sail.
Knots
There are two distinct meanings for "knot". The easiest one is the thing we
tie in a piece of line (rope) to secure it. "A bowline is a useful knot." The
other meaning is more complicated. The other "knot" is a nautical mile per hour - a
rate of speed for boats and planes. It is like a mile per hour used on land, except
that a nautical mile is a little more than a statute (land) mile. Therefore when we
say, "the boat is going 5 knots" we are saying that the boat is going 5 nautical miles
per hour, which is a little more than 5 miles per hour.
[l]
Leech
The longest edge of a sail, the trailing (aft) edge. On the mainsail, it is the only
edge not attached to either the mast or the boom (or the gaff on a gaff-rigged boat). The leech
of the mainsail may have one or two telltales attached to it. They will stream back when the
sail is properly set. If you think of the mainsail as a right triangle, the leech is the
hypotenuse.
Leeward
This word is pronounced "looward" but it means "toward the lee side or toward the side that is
away from the source of the wind." Its opposite is "windward". Sailors are always aware of the
windward and leeward side of the boat. The sails are always set on the leeward side and when a
boat changes tacks, the leeward and windward sides switch their left/right designations.
Lift
A shift in the wind toward the windward side of the boat which will allow a close
hauled boat to "head up" (steer closer to the source of the wind).
Lines
Almost all ropes on a boat are called "lines".
Luff
A fluttering action seen on the sails when the wind is pushing on both sides simultaneously.
When the boat is headed directly into the wind, the sails will be fully luffing. When sailboat
under way is turned slightly toward the source of the wind (or the sail is released until it is
an about a 45 degree angle to the wind) a luff will appear at the foremost edge of the sail,
while the rest of the sail remains full. The luff looks like a dent in the normally concave surface.
The edge of the sail where the luff will first appear is also called the "luff" of the sail.
[m]
Mainsail
The tallest sail on the boat, raised on the mast and fixed to the boom. The other sail on a sloop-rigged boat
(a boat with one mast and two sails) is the jib, which is forward of the mainsail.
Main Sheet
The lines (ropes) on a sailboat that control the set (shape) of the sails
are called sheets. The mainsail is controlled by the mainsheet, one long
line that attaches to the boom and leads to the centerline of the boat just
forward of the wheel. The mainsheet runs through blocks (pulleys) on the
boom and on the hull to make it easier to control. There is a cleat adjacent
to these blocks for securing the mainsheet
Mast
The major vertical spar on a sailboat. A sloop has one mast, a schooner, ketch and yawl all have
two masts.
Momentum
The motion in a given direction, that is entirely the result of the mass of the object moving in that
direction and not to some other force being applied to it. This momentum could also be called "inertia".
When we steer a sailboat into the wind, its momentum carries it a certain direction in that direction,
but it cannot sail in that direction due to the force of the wind on its sails.
Mooring
A very heavy anchor, permanently left on the bottom of a harbor and attached by chain and line to
a buoy (or two) floating on the water's surface. A boat can tie up to such a buoy and be safe from
harm.
[n]
Nautical
Referring to the sea or maritime matters. A "nautical" mile is a measurement of distance on the
sea (or in aviation) which is not the same as a "statute mile", the measure of distance on
land.
[o]
Off the wind
A boat is sailing "off the wind" when it is not "close hauled" which means sailing at as close
an angle as possible to the source of the wind. Anytime a boat is sailing an angle of greater
than about 50 or 60 degrees from the direction of the wind it could be said to be sailing "off
the wind". The names for points of sail that are off the wind are "reaching" and
"running".
Outboard
Outside the hull of the boat, such as an "outboard" motor.
Overheat
Getting too hot for efficient operation. If an engine is not properly cooled it can "overheat",
which may cause permanent damage.
[p]
Pointing
This is one of several terms that refer to the ability of a sailboat to go upwind - toward the
source of the wind. When the sails are close hauled and the boat is traveling efficiently at
an angle of about 45 degrees to the source of the wind, the boat is said to be "pointing." Old
sailing ships using square sails were not as good at "pointing" as newer ships using modern
rigs.
Port
The word used for the left side of boats and airplanes. The color is associated with red. You will
see a red light on the left wing tip of an airplane flying at night and on the left side of a
boat.
Propeller shaft
A steel rod which connects the propeller, which is outside the boat, to the inboard engine.
[q]
[r]
Reaching
Sailing a course, or point of sail that is not close hauled and not running.
A "beam reach" is 90 degrees to the wind direction. A "close reach" is between a
beam reach and sailing close-hauled (45 degrees to the wind). A "broad reach" is
between a beam reach and a run (180 degrees to the wind). Sailing at any of these angles
is reaching.
Rudder
The rudder is a pivoting blade that steers the boat by the force of the water flowing over
the flat vertical surface, capable of inducing drag on one side of the hull or the
other.
Running
Sailing at an angle of 180 degrees to the wind or "downwind". When running the sails are eased,
the jib may be winged opposite the mainsail, and the wind is from behind.
[s]
Sailing close hauled
Sailing at an angle of 45 degrees to the direction of the wind - as close as possible
to this direction.
Sheets
The lines on a sailboat used to control the set of the sails.
Spinnaker
A light, large, balloon-like sail which may be used when sailing off the wind.
Stalled
The condition of having a "full" sail with no air flow over the convex surface.
This is seen when the leeward telltale stops streaming. The significance is that
the sail is not working efficiently and the sail's angle to the wind must change
to get it working again. This is accomplished on a close hauled course by steering
the boat toward the source of the wind. When sailing off the wind, it is accomplished
by easing the sheet to let the sail out.
Starboard
The word used for the right side of boats and airplanes. The color is associated with
starboard is green. You will see a green light on the right wing tip of an airplane flying
at night and on the right side of a boat.
[t]
Tack
Referring to which (of two) positions the sailboat boat may take with respect to the direction
of the wind. If the windward side is starboard, the boat is said to be on the starboard tack. If
the windward side is port, it is on the port tack. Tack, when used as a verb, refers to changing
tacks by coming about (pointing the boat into the wind). It can also refer to the whole process of
moving the boat up wind as in "We had to tack up the river because the wind was against us." It also
means the corner of the sail where the luff (forward edge) meets the foot (bottom edge).
Telltales
Strips of yarn, ribbon, or even audiotape attached to the sails or rigging of a sailboat in order to
reveal the flow of wind at the point where they are attached. Telltales will show that the sail is set
properly for conditions and/or that the boat is in the groove on a close hauled course.
Throttle
The control on an engine that increases or decreases its speed.
Tiller
A handle, usually made from a long stick, that attaches to the top of the rudder and is used to
steer a boat.
Transom
The part of the hull at the very stern of a boat. Outboard motors are usually mounted on the transom of a boat.
That is also where you will usually find the boat's name.
Trim
To adjust a sail by pulling it closer to the boat. Opposite of "ease".
[u]
Under power
Moving a boat with a motor rather than by oars or a sail.
"There was no wind so we had to finish the day's voyage under power."
Under way
Moving, as opposed to staying still. "We left the mooring and got under way
at 0600 hours."
Upwind
Referring to the direction that is toward the source of the wind.
Opposite of "downwind".
[v]
Volatile
Very easy to catch fire or explode.
[w]
Winch
A machine used to trim the sails. It consists of a drum around which a line is wrapped
and an internal ratchet, which allows the drum to turn in one direction. The winch works
as a wheel-and-axle type of machine and it is often equipped with a handle to increase
the mechanical advantage even further.
Wing, winged
When sailing downwind it is possible to fly the jib on the opposite side of the boat from
the mainsail. Such a jib is said to be "winged". And such sailing is called "wing on wing."
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