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Glossary

The vocabulary of offshore racing, explained: boats, keels, foils, rigs, weather, rules and results. 195 terms.

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24-hour recordResults & records
The greatest distance sailed in 24 hours, by type of boat or by class.

A

Air draftDimensions
Height of the boat above the water: from the waterline to the top of the mast.
AISOn-board systems
A system that broadcasts the boat's position, course and identity to nearby ships by radio.
AnticycloneWeather & oceans
An area of high pressure with light wind at its centre; boats sail around it.
Apparent windSailing & navigation
The wind felt on board: the true wind combined with the wind created by the boat's speed.
AppendageKeels, foils & rudders
Everything that sticks out under the hull: keel, foils, daggerboards, rudders.
AutopilotOn-board systems
A computer and actuator that steer the boat instead of the sailor.
Average speedResults & records
Distance divided by time, either along the theoretical route or over the distance actually sailed.

B

BackstayRig
The wire or rope holding the mast from behind; runners are the movable version, one per side.
BeamDimensions
Maximum width of the boat; for a multihull, from one float to the other.
Beaufort scaleWeather & oceans
A scale from 0 to 12 that grades wind strength by its effect on the sea.
Boat captainCrew
Runs the technical preparation of the boat and its shore crew.
BoomRig
The horizontal spar hinged to the mast, holding the foot of the mainsail.
BowHull & structure
The front of the hull, which cuts a way through the water and the waves.
BowspritRig
A spar sticking out beyond the bow to carry the large headsails.
Box ruleRules & safety
A rule that sets limits (dimensions, materials) and leaves designers free within them.
BroachSailing & navigation
The boat escapes the helm and suddenly rounds up into the wind, lying on its side.

C

C-foilKeels, foils & rudders
A foil shaped like an arc: its whole curve lifts, and the boat regulates itself.
CalmWeather & oceans
No wind, or too little to make headway.
Canting keelKeels, foils & rudders
A keel that swings sideways, to windward, to better counter heeling.
Canting mastRig
A mast that can lean sideways, to windward.
CapsizeSailing & navigation
The boat turns over; a pitchpole is a capsize end over end.
Carbon fibreHull & structure
A very stiff and light composite material, the standard of racing boats.
CatamaranHull & structure
A multihull with two identical hulls joined by beams or a platform.
CharterBoat life & partners
Renting a boat for a race or a season.
ChineHull & structure
A lengthwise edge on the hull, where the bottom meets the side.
ClassRacing
A family of boats racing together under the same rules: IMOCA, Ultim, Class40…
Class recordResults & records
The best performance of a class, as its association keeps it.
Class ruleRules & safety
Construction and equipment rules shared by the boats of a class, to keep racing fair.
Close-hauledSailing & navigation
The point of sail closest to the wind that a sailing boat can hold.
Co-skipperCrew
The second sailor of a pair, sharing the running of the boat with the skipper.
CoachroofHull & structure
A raised part of the deck that shelters the interior and protects the cockpit.
CockpitHull & structure
The space set into the deck from which the boat is steered and trimmed.
Code zeroSails
A very large, fairly flat headsail for light air and reaching.
Collision avoidance systemOn-board systems
Cameras and software that spot obstacles ahead of the boat: ships, debris, whales.
CompositeHull & structure
A material made of fibres (glass, carbon, flax…) set in resin.
Corrected timeResults & records
Elapsed time adjusted by a handicap rating, to compare different boats.
CourseRacing
The route set by the organisers: start, marks to round, forbidden zones, finish.
Crewed sailingCrew
Racing with several sailors on board, with shared roles.
CrossbeamHull & structure
A beam joining the hulls of a multihull.

D

DaggerboardKeels, foils & rudders
A retractable vertical fin that stops the boat drifting sideways, without lifting it.
DeckHull & structure
The surface closing the hull on top, where the crew works the boat.
DepressionWeather & oceans
An area of low atmospheric pressure, bringing strong wind and bad weather.
DesignBoat life & partners
The drawing a boat is built from; sister-ships share the same design.
Did not startResults & records
An entered boat that did not start (DNS).
DismastingSailing & navigation
The mast breaking at sea.
DisplacementDimensions
The mass of the boat ready to sail, equal to the mass of water it displaces.
DisqualificationResults & records
Removal from the ranking decided by the jury (DSQ).
Distance to finishResults & records
The distance left to the finish, measured along the shortest route that respects the course.
Distance to leaderResults & records
The gap in miles between a boat and the leader of the provisional ranking.
DivisionResults & records
A group of boats ranked together in a race: a class, or a grouping of mixed boats.
DoldrumsWeather & oceans
An area near the equator, between the trade winds of both hemispheres, made of calms and storms.
Double-handed sailingCrew
Racing with two sailors on board.
DownwindSailing & navigation
Points of sail with the wind coming from behind the boat.
Downwind sail areaDimensions
Sail area carried with the wind on the beam or from behind, with the big headsails.
DraftDimensions
How deep the boat sits: from the waterline to the lowest point of the keel.
Dynamic Stability SystemKeels, foils & rudders
A retractable wing on the leeward side that lifts the hull without making it fly.

E

Elapsed timeResults & records
Time between the boat's start and finish, before penalties.
EPIRBOn-board systems
A beacon that sends the position of a boat or sailor in distress by satellite.
Exclusion zoneRules & safety
An area competitors may not sail in: ice, shipping lanes, protected areas.

F

FinishResults & records
Crossing the finish line, which stops the boat's clock.
Fixed keelKeels, foils & rudders
A keel fixed to the hull, which does not move.
FlagBoat life & partners
The country the boat is registered in.
FloatHull & structure
A side hull of a trimaran, smaller than the central hull.
FlyingSailing & navigation
When the foils lift the hull completely out of the water.
FoilKeels, foils & rudders
An underwater wing that lifts the boat so it drags less in the water and goes faster.
Foil rakeKeels, foils & rudders
The angle of a foil or rudder to the water flow; it sets the lift.
FootDimensions
An imperial unit of length, 0.3048 m, still used to name boats.
ForestayRig
The wire or rope holding the mast forward, on which the headsail is set.
FreeboardDimensions
Height of the hull above the water, from the waterline to the deck.
FrontWeather & oceans
The boundary between two air masses, marked by a wind shift and often rain.
Fuel cellOn-board systems
A silent generator that makes electricity from a fuel (methanol, hydrogen) without burning it.
FurlerSails
A system that rolls a headsail up on itself to stow it without lowering it.

G

GateRacing
A virtual line between two points that boats must cross.
GenerationBoat life & partners
Build period: boats of the same generation often share the same technical choices.
GennakerSails
A large, light and full headsail for reaching and downwind sailing.
Glass fibreHull & structure
A composite material heavier and cheaper than carbon, common in production boats.
Great capesWeather & oceans
The capes of Good Hope, Leeuwin and Horn, the milestones of a round-the-world voyage through the Southern Ocean.
Great circleSailing & navigation
The shortest path between two points on the globe, which looks curved on a chart.
GRIB fileWeather & oceans
A compact weather forecast file (wind, pressure, waves) read by routing software.
GrinderCrew
The crew member who works the pedestal grinder to turn the winches.
GustWeather & oceans
A brief increase in wind strength above the average.
GybeSailing & navigation
Changing the side the wind comes from by turning the stern through the wind.

H

HalyardRig
The line used to hoist a sail.
HeadsailSails
A sail set in front of the mast; upwind it is a jib (J1, J2, J3 from largest to smallest).
HeelSailing & navigation
The boat leaning over to one side under the force of the wind.
HelmCrew
The crew member who steers the boat.
HullHull & structure
The body of the boat: the part that floats and carries the deck, the rig and the appendages.
Hull lengthDimensions
Length of the hull alone, without the bowsprit or protruding appendages.
Hydraulic ramKeels, foils & rudders
A hydraulic piston that swings a canting keel or adjusts an appendage.
HydrogeneratorOn-board systems
A small propeller trailing at the stern that makes electricity as the boat moves.

I

Ice limitRules & safety
A line south of which competitors may not sail, to avoid icebergs.
In-port raceRacing
A short race sailed near a port, in front of spectators, alongside an offshore race.
Inverted bowHull & structure
A bow that slopes backwards from the waterline up to the deck, instead of forwards.

J

J-foilKeels, foils & rudders
A foil whose lower part curves into a hook, between the C and the L.
JuryRules & safety
The body that hears protests and decides penalties and redress.
Jury rigSailing & navigation
A makeshift mast rigged with what is on board after a dismasting.

K

KeelKeels, foils & rudders
The weighted fin under a monohull's hull, which stops it drifting sideways and keeps it upright.
Keel bulbKeels, foils & rudders
A streamlined lead weight at the bottom of the keel, putting the ballast as low as possible.
KnotSailing & navigation
The unit of speed at sea: one nautical mile per hour, or 1.852 km/h.

L

L-foilKeels, foils & rudders
A foil made of a vertical shaft and an almost horizontal wing: it makes the boat fly.
LaunchBoat life & partners
The moment a new boat touches the water for the first time.
LeaseBoat life & partners
Renting a boat for a long period, often a whole campaign.
LegRacing
One section of a stage race, from one port to another.
Length overallDimensions
The total length of the boat, from the tip of the bowsprit to the back of the rudders.
Life raftRules & safety
An inflatable raft, with supplies and equipment, where the crew takes refuge if the boat must be abandoned.
Lifting keelKeels, foils & rudders
A keel that can be raised into the hull to reduce draft.

M

MainsailSails
The main sail, set behind the mast and held by the boom.
MastRig
The vertical spar that carries the sails.
MonohullHull & structure
A boat with a single hull, kept upright by the weight of its keel.
MouldBoat life & partners
The form in which a hull or composite part is built; it can be used for several boats.
MultihullHull & structure
A boat with several hulls, a catamaran or a trimaran, stable thanks to its width rather than to ballast.

N

Nautical mileSailing & navigation
The unit of distance at sea: 1,852 metres.
Naval architectBoat life & partners
The designer of the boat: hull shape, appendages, structure, sail plan.
NavigatorCrew
The crew member who plans the route: weather, strategy and positioning.
Non-stopRacing
A race sailed in one go, without stopping in port or receiving help.
Notice of raceRules & safety
The document that announces a race and sets its conditions: dates, eligible classes, qualification, special rules.

O

Official timeResults & records
Elapsed time with the jury's penalties added and redress taken off.
Offshore racingRacing
Sailing races on the open sea, over days or weeks, far from the coast.
On-board energyOn-board systems
How the boat makes and stores its electricity: solar panels, hydrogenerators, engine…
Onboard reporterCrew
Crew member who films and reports during the race, without sailing the boat.
One-designRules & safety
A class where all boats are identical: only the sailors' skill makes the difference.
Outside assistanceRules & safety
Any material help received from outside during the race, forbidden in unassisted races.

P

PenaltyResults & records
Time added by the jury to a boat's elapsed time for breaking a rule.
Pit stopRacing
A stop in port for repairs, allowed or not depending on the race rules.
PlaningSailing & navigation
When the hull skims over the water instead of pushing it aside, allowing much higher speeds.
Point of sailSailing & navigation
The boat's direction relative to the wind: close-hauled, beam reach, broad reach, running.
PolarSailing & navigation
A table of a boat's speeds for each wind strength and angle.
PrepregHull & structure
Fibre cloth already impregnated with resin, cured in an oven or autoclave to harden.

Q

QualificationRules & safety
The conditions to meet to be allowed to start: solo passage, races sailed, miles covered.

R

Race recordResults & records
The best time ever on a race's course.
Racing Rules of SailingRules & safety
The international rulebook of sailing races, published by World Sailing every four years.
RankingResults & records
The order of boats at a race's finish, within their division or across all classes (line honours).
ReachingSailing & navigation
Points of sail with the wind from the side, from beam reach to broad reach; often the fastest.
RecordResults & records
The best ratified performance over a course or a duration, in a race or an attempt.
RedressResults & records
Time given back by the jury, for instance after diverting to assist another boat.
ReefSails
Reducing the mainsail's area by lowering and tying down its bottom part.
RefitBoat life & partners
A major yard period modernising an existing boat: new foils, new deck, reinforcements…
RetirementResults & records
The boat started but did not finish the race (DNF).
RigRig
The mast, its boom and all the wires and lines that hold them and control the sails.
Righting momentDimensions
The force with which the boat resists heeling; it sets how much sail it can carry.
Roaring FortiesWeather & oceans
Southern latitudes between 40° and 50° South, swept by strong westerlies; further south, the Furious Fifties.
RookieCrew
A sailor taking part in a race for the first time.
Rotating mastRig
A mast that turns on itself to line up with the sail, for a cleaner airflow.
Round-the-world raceRacing
A race around the planet, generally via the three great capes and the Southern Ocean.
RouterCrew
Weather specialist who advises on the route, often from shore.
RudderKeels, foils & rudders
The pivoting fin at the back that steers the boat.

S

Safety equipmentRules & safety
The mandatory safety gear on board, checked before the start.
Sail numberBoat life & partners
The identifier printed on the mainsail: a country code followed by a number.
Sail planSails
All the sails of a boat and how they are arranged.
Sailing instructionsRules & safety
The document describing how the race is run: course, marks, forbidden zones, times, penalties.
Sandwich constructionHull & structure
A panel made of two composite skins bonded on either side of a light core.
Satellite communicationsOn-board systems
Satellite links connecting the boat to land: weather files, videos, calls.
Scow bowHull & structure
A very wide, rounded bow, shaped like a spoon, that rides over the waves.
Sealed engineRules & safety
In racing, the propeller shaft is sealed: the engine may charge batteries but not drive the boat.
SheetRig
The line that sets the angle of a sail to the wind.
ShipyardBoat life & partners
The company that builds the boat, or carries out major work on it.
ShroudRig
A wire or rope that holds the mast up from the sides.
Single-handed sailingCrew
Racing with a single sailor on board.
Sister-shipBoat life & partners
A boat built to the same design as another.
SkipperCrew
The sailor in command of the boat, responsible for it in the race.
Solar panelOn-board systems
A flexible or rigid photovoltaic panel fitted to the deck or coachroof.
SpreaderRig
A horizontal strut on the mast that holds the shrouds out to support it better.
SquallWeather & oceans
A sudden, short burst of wind under a cloud, often with rain.
Stability testRules & safety
A check that the boat rights itself after a capsize and cannot sink.
Stage raceRacing
A race split into several legs, with stops in intermediate ports.
StartRacing
Crossing the line between the committee boat and a buoy at the starting signal.
StaysailSails
A small headsail set on an inner forestay, for strong wind.
SternHull & structure
The back of the hull; the transom is its flat, vertical end.
SwellWeather & oceans
Long, regular waves formed by distant wind; wind waves are raised by the local wind.

T

T-foilKeels, foils & rudders
A vertical fin with a horizontal wing at its tip, often on rudders.
TackSailing & navigation
Changing the side the wind comes from by turning the bow through the wind.
TeamBoat life & partners
The organisation running one or more racing boats: technical crew, logistics, partners.
Title sponsorBoat life & partners
The company that gives its name to the boat or team.
TrackerRacing
A beacon that regularly sends the boat's position, shown on the race map.
Trade windsWeather & oceans
Steady winds blowing towards the equator, from the northeast in the northern hemisphere and the southeast in the south.
Transatlantic raceRacing
A race across the Atlantic Ocean, most often from Europe to the Caribbean or South America.
TrimaranHull & structure
A multihull with three hulls: a central hull and two side floats.
TrimmerCrew
The crew member who constantly adjusts the sails to the wind.
True windSailing & navigation
The wind as it blows, measured against the sea, regardless of the boat.

U

U-foilKeels, foils & rudders
A foil whose tip turns back up, forming a U, to keep lift as it rises out of the water.
UFOSailing & navigation
Unidentified floating object: a container, log, debris or sea animal hit at sea.
Upwind sail areaDimensions
Sail area carried when the boat sails towards the wind: mainsail and headsail.

V

Velocity made goodSailing & navigation
The speed at which the boat actually gets closer to its goal.
VentilationKeels, foils & rudders
When air or vapour forms on a foil and makes it suddenly lose lift.

W

Water ballastOn-board systems
A tank filled with seawater on the windward side to add weight and stability.
Waterline lengthDimensions
The length of hull in contact with the water when the boat is at rest.
WatermakerOn-board systems
A device that makes fresh water from seawater.
Wave-piercing bowHull & structure
A fine, sharp bow that cuts through the waves instead of riding over them.
WaypointRacing
A point the course requires boats to round or pass: a buoy, an island, a cape or coordinates.
Weather routingSailing & navigation
Working out the fastest route from weather forecasts and the boat's performance.
WinchRig
A drum that multiplies force to pull in a sheet or halyard.
Wing mastRig
A mast shaped like a wing, which works as part of the sail plan.
WithdrawalResults & records
An entered boat that withdrew before the start.
WSSRC recordResults & records
A record ratified by the World Sailing Speed Record Council, which checks sailing records.