A Glossary of Nautical Terms for the Budding Sailors Among Us
Ahoy, Sailors and Sailing Newbies alike! It is by no means complete, but still extensive enough to include terms not commonly used but left included purely for interest sake.
Maybe you’re very new to sailing and wondering what all these people are talking about. Maybe you’re wanting to sound a little more authoritative when talking to other sailors, or maybe you want to instill some confidence in non-sailors who you’re trying to coax aboard your tiny little, or rickety looking, barely floating project. Whatever your reason for clicking your way to this page, you may have stumbled into something.
Here we have, as the title suggests, a glossary of nautical terms.
A
ABAFT
Toward the stern of the vessel.
ABEAM
At a right-angle to the boat’s center-line.
AFT
In, on, or towards the stern of the vessel.
AHULL
A controversial storm weathering tactic of lashing the helm to the leeward side with no sails set.
AMIDSHIPS
The center area of the vessel between the fore-and-aft.
APPARENT WIND
The speed and direction of the wind combined with the boat’s movement and the true wind speed and direction.
ASTERN
Behind the vessel
ATHARTSHIPS
A direction perpendicular to the center line of the vessel.
AZIMUTH
The act of measuring the angular distance on the horizon circle in a clockwise method, typically between a heavenly body and an observer.
B
BACK
When the wind starts to shift in an counter-clockwise direction.
BACKSTAY
The stay supports the mast from the stern.
BACKWINDED (Aback)
A sheeted sail with the wind filling the sail on the leeward side.
BAGGYWRINKLE
A soft covering for the shrouds to reduce sail chafe
BALLAST
Usually a lead-filled keel for stabilization of the boat.
BALLAST KEEL
A ballast bolted to the keel, increasing the vessel’s stability to prevent capsizing.
BATTEN
A flexible and lightweight strip feeds into the sail leech’s batten pocket, supporting the roach.
BEAM
The widest point of the vessel – “On the beam”, objects are at a right-angle to the center-line
A traverse member supporting the deck
BEAR AWAY
Taking the action of steering the vessel away from the wind.
BEARING
The object’s direction from the observer measured in magnetic or true degrees.
BEAT
Tacking up wind, close-hauled with alternating tacks.
BELAY
To fasten the rope around the cleat using a figure-8 knot.
BEND
Securing the sail to the spar before hoisting it or connecting two ropes using a knot.
BERTH
A sleeping quarters on a boat or a slip occupied by a vessel in a dock system.
BIGHT
The loop or bend in a knot.
BILGE
The depths of the hull where water collects.
BLOCK
A sheave fixed inside a frame with a line (rope) running around it, changing the direction of the run and/or increasing purchase.
BOLO
Acronym for Be On the Look Out for a missing vessel or its crew
BOWSPRIT
A spar extending forward from the vessel’s bow.
BROACH
The heeling action of the boat when it slews to the broadside while running downwind. A broach usually occurs in heavy seas.
BROAD REACH
The point of sailing the vessel between dead downwind and a beam reach with the wind coming onto the quarter.
BULKHEAD
A partitioning wall in the vessel in an athwartships orientation.
C
CABLE
A measurement of distance equal to 0.1 of a nautical mile (607.6115 ft), 185-meters, or approximately 100 Fathoms.
CENTREBOARD
A retractable hull appendage pivoting out of a slot in the hull of a sailboat to move the centre of lateral resistance, to reduce drag, and for reducing leeway.
CHART DATUM
The reference level on the charts below which the low tide level. The sounding features below the chart datum. The datum level varies depending on country and area.
CLAW RING
The fitting slipping over the boom like a claw. It attaches to the main sheet after you finish reefing the sail.
CLEAT
The metal, wooden, or plastic fitting used to secure ropes.
CLEW
The lower, aft corner of the sail where the leech and foot meet.
CLOSE-HAULED
The closest point of sail to the direction the wind is coming from, AKA beating.
CLOSE REACH
The point of sail between the beam reach and close-hauled points with the wind ahead of the beam.
COURSE
The plotted path that the vessel will be steered to or the current direction in which the vessel is being steered. Usually expressed in true or magnetic degrees.
CRINGLE
The rope loop at either end of the line reef points or an eye in a sail.
CUTTER RIG
A sailboat with a second forestay secured to the mast roughly one third of the distance from the masthead to the deck, with the purpose of carrying a Staysail. This rig also employs running backstays to counter the pull of the staysail on that section of the mast, keeping the mast in column.
D
DEAD RUN
Sailing with the wind blowing to the aft, in line with the center-line of the vessel.
DEVIATION
The difference between the direction indicated by the magnetic north and the compass needle. The deviation is caused by ferromagnetic objects aboard the vessel.
DISPLACEMENT
The weight of the water that is displaced by the weight of the boat as it floats.
DOWNHAUL
A line (rope) used to pull down a spar or sail.
DRAFT
The vertical distance between the lowest point on the keel and the waterline of the vessel.
DROGUE
A sea anchor thrown over the stern of a life raft or boat or to reduce drift.
DROP KEEL
A retractable keel drawn into the vessel’s hull.
DSC
Acronym for Digital Selective Calling (a function on Marine radios).
E
EPIRB
Acronym for Emergency Position Indicating Radio Beacon.
ETD
Estimated Time of Departure.
ETA
Estimated Time of Arrival.
F
FAIRLEAD
A line guide to prevent chafe while allowing the line to change direction. AKA as a chock when used for docklines
FATHOM
Equal to 6 feet, or 1.83 meters.
FIDDLE
The raised border on tables and counters to prevent objects from falling.
FIX
The vessel position plotted by two or more bearings on fixed points of reference (ie island, buildings, or other immovable objects.
FORESTAY
The stay running between the masthead and stemhead (The bow or bowsprit) and acting directly against the opposing tension from the backstay, to secure the masthead.
FREEBOARD
The vertical distance between the top of the deck and the waterline.
FURLER
A connected set of extruded aluminum sections comprising the foil and surrounding the forestay, featuring a groove accepting the luff of the headsail, and a drum which is turned by way of a furling line. Actuating the drum wraps the sail around the foil.
G
GENOA
A large-size headsail, overlapping the mainsail.
GIMBAL
A hanging, mount system based on two pivot-points to keep objects horizontal regardless of the vertical angle of the boat.
GO ABOUT
To change tack by turning the boat into and through the wind.
GOOSEWING
Booming out the headsail in a windward position using the whisker pole to hold it on the opposite side of the mainsail.
GOOSENECK
The fitting anchoring the mast to the boom, allowing free movement in all directions.
GPS
Acronym for Global Positioning System.
GUY
One of two lines positioning and securing the spinnaker pole laterally.
GYBE
Turning the stern through the wind to change from one tack to another.
H
HALYARD
The line for hoisting the lowering sails.
HANK
The fitting for attaching the sail’s luff to a stay when no furling system exists.
HAT
Acronym for Highest Astronomical Tide.
HATCH
A watertight, deck-fitted port that opens and closes providing light and fresh air to the cabin interior and an emergency escape for the crew.
HEAD
The toilet.
HEADWAY
The forward motion of the vessel through the water.
HEAVE-TO
A storm tactic the sails are backwinded and the helm is lashed opposite.
HEEL
When the vessel exaggeratedly leans to one side.
J
JACK LINES
The line running from aft-to-fore on both sides of the vessel. The jackstays allow for the clipping attachment of safety harnesses to prevent being lost at sea when falling overboard.
JURY RIG
A temporary device for replacing damaged or lost gear.
K
KEDGE
A secondary, smaller, lightweight anchor. To use such anchor to drag a grounded boat back to deeper water
KEEL
The main structural member and backbone of a sailboat, running along the centre of the bottom and providing ballast.
KETCH
A dual-masted sailboat featuring a mizzen mast that’s slightly smaller than its mainmast, with a stepped forward position of the rudder post/stock.
L
LANYARD
A short length of line attached to an important object that you don’t want to lose. The lanyard can connect to your wrist or lifejacket.
LAT
Short form for Latitude.
LEECH
The aft edge of the Marconi sail or both vertical edges of a square sail.
LEE HELM
The natural tendency of vessels to bear away from the direction of the wind.
LEE SHORE
A shore onto which an onshore wind is blowing.
LEEWARD
Moving in a direction away from the wind. The direction in which the wind is blowing.
LEEWAY
The sideways motion off course resulting from the wind blowing on one side of the hull and sails.
LIST
The vessel’s leaning to one side due to improper distribution of weight in the boat’s hull.
LOG
The instrument for measuring the distance and speed of a boat traveling through the water. A record of the details of a voyage in a logbook.
LUFF
noun: The leading edge of the sail.
verb: A sail is said to be luffing when it begins to flog as the wind is spilled from it. Luffing up is the act of turning the boat into the wind.
M
MAST STEP
The keel socket locating the base of the mast.
MAYDAY
An emergency call involving a life or death situation requesting immediate assistance.
MERIDIAN
The imaginary longitudinal line circling the earth, passing through both poles.
MIZZEN
The short after-most mast on the yawl or ketch.
O
OUTHAUL
The rope used for pulling out a sail’s foot.
P
PAINTER
The bowline on a tender or dinghy for towing or making fast.
PAN PAN
An emergency call not involving a life or death situation requesting immediate assistance.
PAY OUT
To gradually let out line.
POINT OF SAIL
A boat’s course relative to the direction of the wind.
PORT
The left-hand side of the vessel when looking forward.
PORT TACK
A vessel is on a port tack when the wind is atTACKing the port side of the boat, and the sails are to the starboard side.
PULPIT
The steel guard rail fitted to the bow to provide additional safety for the crew when working around the boat’s edge.
PUSHPIT
The steel guard rail fitted around the stern of the boat to prevent the crew from falling overboard.
Q
QUARTER
The section of the vessel midway between the beam and the stern.
R
REACH
To sail within the range of three points of sail, with the wind blowing onto the beam, including a close reach, a beam reach, and a broad reach.
REEF
The act of reducing the sail surface area through folding or rolling additional materials onto the forestay or boom.
REEFING PENNANT
The line allowing you to pull down the leech cringle or luff to the boom while reefing.
RHUMB LINE
The plotted line of the vessel’s course on a chart.
RIDING SAIL
A small sail hoisted to maintain steerage underway during stormy weather,
Also, a small sail hoisted near the stern when at anchor, to keep the boat from yawing excessively.
RIGGING SCREW (Turnbuckle)
The deck fitting allowing for tensioning of the standing rigging.
ROACH
The curve in a leech sail extending beyond the direct line formed from clew to head.
RUN
A point of sail with the wind on the stern and with the sails eased fully to collect maximum wind.
RUNNING RIGGING
All working lines such as halyards and sheets used for trimming and setting sails, and other tasks.
S
SCHOONER
A vessel with two or more masts and the tallest, mainmast aft of the others.
SCUPPERS
Drain holes allowing water to drain off the deck, either through the deck and plumbed through the hull, or through the bulwarks.
SEA ROOM
The room in which the vessel can maneuver clear of submerged dangers.
SEACOCK
The shut-off valve for the underwater outlet or inlet passing through the vessel’s hull.
SEELONCE
Radio Silence (french). Used when reporting a distress call or incident at sea.
SECURITE (Securité)
A radio call for identifying and reporting uncharted hazards to mariners.
SET
The act of hoisting a sail. Or how the sails fit or the direction of a tidal stream or current.
SHACKLE
A steel link featuring a removable bolt crossing the open end.
SHEET
A control line running from the clew of a sail to a winch allowing for the trimming and control over the sail.
SHROUDS
The cable or rope part of the standing rigging leading from their connections to the mast to the chainplates at the deck level restraining the mast from sideways movement, and keeping it in column.
SLOOP
A boat with a single-masted design for one headsail and one mainsail.
SPAR
The general term for any metal or wooden pole on board a boat.
SPINNAKER
A lightweight, large balloon-shaped sail for running or reaching.
SPREADERS
The horizontal struts attach to the mast and extend to the shrouds to assist with supporting the mast.
STANCHION
The metal post bolted to the deck in an upright position to support the guard railing or lifelines.
STANDING RIGGING
The stays and shrouds provide permanent support to the mast.
STARBOARD
The right-hand side of the vessel when looking forward.
STARBOARD TACK
A vessel is on a starboard tack when the wind is atTACKing the starboard side of the boat, and the sails are to the port side.
STAY
The rope or wire that supports the mast in the fore-and-aft direction.
STEERAGE WAY
The vessel has steerage when it reaches sufficient speed, allowing for steering or answering the helm.
STROP
A loop of line that attaches a spar to a block to make a sling.
T
TACK
The bottom, forward corner of a sail.
The windward side of a sailboat while under way.
The action of turning the boat through the wind to change tacks.
TAFFRAIL
An elegant wooden railing around a traditional vessel’s stern to prevent crew from falling overboard.
TAIL
To pull on the end of the rope or cable, wound around a winch.
TANG
Sturdy steel fittings used for attaching standing rigging to the spar or mast.
TELL-TALE
Pieces of yarn attached to sails to aid in trimming the sail. Also, a compass mounted over the captain’s berth, allowing for the easy reference to the ship’s course.
TENDER
A description for any small boat that is carried on, or towed by the mothership. Primarily for ferrying crew and supplies and between the mothership and shore.
TERMINALS
The metal fitting forming eyes at the end of cables, wires, or ropes.
THERMAL WIND
The wind that occurs as a result of the difference in temperature between the sea and land. The resulting onshore wind from the sea replaces air rising from land.
THUMB CLEAT
A small cleat featuring a single horn.
TIDAL RANGE
The difference in water levels between the high and low tides is the range of tides.
TOE RAIL
The rail mounted to the edge of the deck.
TOPPING LIFT
The rope linking the mast to the boom end, supporting the boom. Also found on the spinnaker pole or whisker pole.
TOPSIDES
The sides of the hull between the waterline and the deck.
TRACK
The course of the boat making good on its travel plan.
A groove or rail on the boom, or mast accepting a sail’s sliders
A rail with a sliding car to adjust the angle of a sheet.
A similar rail with cars on which the traveler runs for adjusting mainsheet trim.
TRANSOM
A flat surface forming the stern of a boat. Also, a horizontal beam reinforcing the stern of a boat.
TRICK
A watch period or watch duty at the helm of the vessel.
TRI-COLOR LAMP
A lamp displaying red in proper port sectors, green in the starboard sectors, and white astern.
TRIM
To adjust the sail angle using sheets to achieve optimal efficiency from the sail.
TRUE WIND
The speed and direction of the wind when anchored, stationary on the water, or land.
TURK’S HEAD
A decorative knot featuring variable numbers of interwoven strands that form a closed loop.
TURNBUCKLE (Rigging Screw)
The apparatus used for tightening the standing rigging on the vessel.
U
UNDERWAY
The vessel is underway when it releases it fastening to shore when it is not aground or at anchor.
V
VANG
A boom vang or kicking strap is a line or piston system on a sailboat used to exert downward force on the boom, controlling the shape of the sail.
VEER
The wind will veer when shifting in a clockwise direction. Veering can also mean paying out anchor rope or cable in a controlled manner.
W
WAKE
The v-shaped progression of the wave, started by the bow wave, as it moves laterally outward from a boat as it moves forward in the water.
WAVELENGTH
The distance between the radio waves.
WEATHER HELM
The tendency of the vessel to turn into the wind.
WHISKER POLE
A lightweight pole used for holding the clew of the headsail out when on a run.
WINCH
A sailboat winch is traditionally hand driven with a removable handle, used for deploying and trimming sheets. Electrically powered winches are also available.
WINDAGE
The parts of the vessel that increase the drag on the boat. Examples would be the spars, rigging, dodgers, and other structures mounted on the exterior of the boat.
WINDLASS
The windlass is another winch used for deploying and retrieving an anchor. They can be manual, electric.
WINDWARD
The direction from which the wind blows toward the wind (the opposite way to leeward).
X
XTE
Cross Track Error. The perpendicular distance between the vessel’s current position and its rhumbline.
Y
YAWL
A dual-masted vessel with its mizzen stepped aft of its rudder post/stock.
