abandon ship - An imperative to leave the vessel immediately, usually in the face of some imminent danger
anchor - A heavy metal object designed to prevent or slow the drift of a ship
apparent wind - A combination of the true wind direction and the headwind created by a yacht’s forward motion
ashore - On the shore. Not on the yacht
aboard - On or within the vessel
aft - At, near or towards the stern, to move aft is to move back
adrift - Floating free with the currents and tide
ahoy - A cry to draw attention
anchorage - A suitable place for a ship to anchor in relation to the wind, seas and bottom
attached flow - Air flowing with minimum turbulence across both sides of a sail
backwind bubble - The effect create by easing a sail so that leading edge is blown slightly to windward
bad air - The turbulent or disturbed air that exists to leeward of a boat under sail
baggywrinkle - A soft covering for cables that stops sails chafing
bareboat - A boat hired without a crew
bailer - A device for removing water that has entered the boat
bar - Large mass of sand or earth, formed by the surge of the sea
barging - An attempt by a boat to squeeze across the starting line immediately to leeward of the committee boat
batten down the hatches - Secure hatches and other loose objects within hull and on deck, to prepare for inclement weather
beam - the greatest width of the boat
bear away - turn away from the wind
bear away set - A spinnaker set executed at the windward mark
berth - A bed or sleeping accommodation on a boat or place where the ship can tie up or anchor
bend - For and aft curvature induced in the mast
bilge - The compartment at the bottom of the hull of a ship or boat where water collects and must be pumped out of the vessel
boom - A pole running at a right angle from the mast
boom vang - Primarily used to control leech tension on a reach or run
bow - The front of a ship
bowline - Important knot used to form a fixed loop at the end of a rope. It has the virtues of being both easy to tie and untie
broach - When a sailing vessel loses control of its motion and is forced into a sudden sharp turn, often heeling heavily and in smaller vessels sometimes leading to a capsize
bulkhead - An upright wall within the hull of a ship separating its compartments
buoy - A floating object which is anchored at a given position and serves as an aid to navigation or for mooring
burgee - A small flag, typically triangular, flown from the masthead of a yacht to indicate yacht-club membership
cable - A large rope
capsize - When a ship or boat lists too far and rolls over, exposing the keel
camber - The horizontal curvature of a sail as viewed between the luff and the leech
catamaran - A vessel with two hulls
centreboard - A board or plate lowered through the hull of a dinghy on the centreline to resist leeway
chafing - Wear on line or sail caused by constant rubbing against another surface
chain locker - A space in the forward part of the ship, typically beneath the bow in front of the foremost collision bulkhead, that contains the anchor chain when the anchor is secured for sea
chock - A fitting through which anchor or mooring lines are led
compass - Navigational instrument showing the direction of the vessel in relation to the Earth's magnetic poles
Committee boat - Boat aboard which the race committee administers the race
cleat - A fitting to which lines are made fast
clove hitch - A knot for temporarily fastening a line to a spar
coaming - The raised edge of a hatch, cockpit or skylight to help keep out water
cockpit - The location from which the boat is steered, usually in the middle or at the stern of the boat
coil - To lay a line down in circular turns
course - The direction in which a vessel is steered
current - The horizontal movement of water
cunningham - Used to control luff tension
davit - Device (like a small crane) for lifting a tender on and off a boat
dead ahead - Exactly ahead, directly ahead
dead astern - A position directly aft or behind the vessel
dead reckoning - Navigating
decks - A permanent covering over a compartment, hull or any part of a ship serving as a floor
dinghy - A small open boat
displacement - The weight of a floating boat measured as the weight of the amount of water it displaces
dock - A protected water area in which vessels are moored. The term is often used to denote a pier or a wharf
draft - The depth of a ship's keel below the waterline
drifter - Especially light winds
ebb - A receding current, when the falling tide recedes out to sea and the water level lowers
ensign - A flag indicating the nationality of a vessel
EPIRB - Emergency Position Indicating Radio Beacon
fast - Fastened or held firmly
fender - An air or foam filled bumper used in boating to keep boats from banging into docks or each other
fetch - The distance across water which a wind or waves have travelled
flare - A pyrotechnic signalling device, usually used to indicate distress
flat sail - A sail with shallow draft
fleet - A group of boats racing together
forepeak - A compartment in the bow of a small boat
foot - Bottom edge of a sail
fouled - Any piece of equipment that is jammed, clogged, entangled or dirtied
galley - the kitchen of the ship
gangplank - A movable bridge used in boarding or leaving a ship at a pier
gangway - An opening in the bulwark of the ship to allow passengers to board or leave the ship
ground - The bed of the sea
grounding - When a ship touches the bed of the sea
gale - a very strong wind
gunwales - The upper edge of a boat's sides
gybe - Turning the boat so that the stern crosses the wind
hail - To signal another boat verbally, with or without a radio
harbor - A safe place to anchor, protected from the weather. Harbours can be man-made or natural and are used for docking and loading
hatch - A covered opening in a ship's deck through which cargo can be loaded or access made to a lower deck
head - The upper corner of a triangular sail
heading - The direction in which a vessel's bow points at any given time
headway - The forward motion of a boat
heave - A vessel's transient, vertical, up-and-down motion
heave to - Steering into the wind and sea, making minimum headway
helm - The wheel or tiller controlling the rudder
helmsman - A person who steers a ship
hitch - A knot used to tie a rope or line to a fixed object
hull - The main body of the vessel
jib - The next most common sail on any boat. The jib can always be found forward of the mast, and unlike the mainsail, does not have a boom
in irons - When the bow of a sailboat is headed into the wind and the boat has stalled and is unable to manoeuvre
IMS - International Measurement System, a handicapping system
Jacobs Ladder - A rope ladder, lowered from the deck, as when pilots or passengers come aboard
jetty - A structure, usually masonry, projecting out from the shore; a jetty may protect a harbor entrance
keel - The bottom-most longitudinal structural element on a vessel
land lubber - A person unfamiliar with being on the sea
latitiude - The distance north or south of the equator measured and expressed in degrees
lazarette - Small stowage locker at the aft end of a boat
lee side - The side of a ship sheltered from the wind
leeway - The sideways movement of the boat caused by either wind or current
leeward - The direction downwind from the point of reference
length overall - LOA - the total length of a boat
lifejacket - Inflatable jacket which keeps a person afloat in the water
lifeboat - A small, often inflatable vessel kept on board a ship and used to take crew and passengers to safety in the event of the ship being abandoned
life buoy - Floating safety ring to assist in a person overboard
line - the correct nautical term for the majority of the cordage or 'ropes' used on a vessel. A line will always have a more specific name, which describes its use
log - A record of courses or operation. Also, a device to measure speed
longitude - The distance in degrees east or west of the meridian at Greenwich, England
luffing - sail flapping
mainsheet - Line that controls the position of the mainsail
man overboard! - A cry let out when a person has gone 'overboard' (fallen into the water)
marina - A place where boats can find fuel, water and other services
mark - An object used as a reference point while navigating
mast - A vertical pole on a ship which supports sails or rigging
mess - An eating place aboard ship
midship - Approximately in the location equally distant from the bow and stern
moor - Yo attach a boat to a mooring buoy or post. Also, to dock a ship
nautical mile - A distance of 1.852 kilometres (1.151 mi). Approximately the distance of one minute of arc of latitude on the Earth's surface. A speed of one nautical mile per hour is called a knot
navigation - The art and science of conducting a boat safely from one point to another
navigation lights - Red, green and white lights required by vessels between sunset and sunrise and in restricted visibility
navigation rules - Rules governing the movement of vessels in relation to each other, provide guidance on how to avoid a collision and are also used to assign blame when a collision does occur
outward bound - To leave the safety of port, heading for the open ocean
outhaul - An adjuster that tensions the sail's foot
overlap - A condition in which any portion of one boat is abeam of any portion of another boat
PFD - Personal Flotation Device - Lifejacket
pier - A loading platform extending at an angle from the shore
pin - The bouy designating the port end of the starting line
pinch - To sail closer to the wind than ones usual close-hauled course
pitch - A vessel's motion, rotating about the beam axis, so the bow pitches up and down
planing - When a fast-moving vessel skims over the water instead of pushing through it
point of sail - The boat’s direction relative to the wind. You cannot sail directly into the wind
plimsol line - The mark on the hull of a ship that shows where the waterline is when the boat is at full capacity
polar diagram - A diagram shoing a boats theoretical optimal speed at different angles of sail
port - Towards the left-hand side of the ship facing forward. Denoted with a red light at night
porthole - An opening in a ship's side, typically a round one for admitting light and air, fitted with thick glass and, often, a hinged metal cover, a window
port tack - Sailing with the wind coming from the port side of the vessel. Must give way to boats on starboard tack.
rake - The degree of which a mast is set to lean aft of vertical
radar reflector - A special fixture fitted to a vessel or incorporated into the design of certain aids to navigation to enhance their ability to reflect radar energy.
reaching - Sailing across the wind: from about 60° to about 160° off the wind
reefing - To temporarily reduce the area of a sail exposed to the wind, usually to guard against adverse effects of strong wind
rigging - The system of masts and lines on ships
ropes - In general, cordage as it is purchased at the store. When it comes aboard a vessel and is put to use it becomes line
roll - A vessel's motion rotating from side to side, about the fore-aft/longitudinal axis
rudder - An underwater vertical plate or board for steering a boat
running - Sailing before the wind with the sail out
sail trim - The position of the sails relative to the wind and desired point of sail
screw - A boat's propeller
seamanship - All the arts and skills of boat handling, ranging from maintenence and repairs to piloting, sail handling and rigging
seaworthy - Certified for, and capable of, safely sailing at sea
set - direction toward which the current is flowing
sextant - A navigational instrument used to determine the vertical position of an object such as the sun, moon or stars. Used with celestial navigation
ship - A larger vessel usually thought of as being used for ocean travel. A vessel able to carry a 'boat' on board
skipper - The captain of a ship
slack - Not fastened; loose
spring line - A pivot line used in docking, undocking, or to prevent the boat from moving forward or astern while made fast to a dock
squall - A sudden, violent wind often accompanied by rain
starboard - The right side of a boat when looking forward. Denoted with a green light at night
starboard tack - Wind across the starboard side. Has right of way over boats on port tack
stern - The rear part of a ship
strong breeze - a wind of force 6 on the Beaufort scale (22–27 knots)
stern Line - A docking line leading from the stern
stow - To put an item in its proper place
sway - A vessel's lateral motion from side to side
tack - To tack is to change direction by turning the bow of the boat through the wind
tell-tale - A piece of yarn or fabric attached to a sail
tide - The periodic rise and fall of water level in the oceans
tiller - A bar or handle for turning a boat's rudder or an outboard motor
transom - The stern cross-section of a square sterned boat
trim - Fore and aft balance of a boat
true bearing - An absolute bearing using true north
true north - The direction of the geographical North Pole
twist - The degree to which the trailing edge of the sail angles off to leeward
weather side - The side of a ship exposed to the wind
weather helm - when the boats natural tendency is to want to change course to windward
wake - Turbulence behind a vessel
wash - The waves created by a vessel
waterline - A line painted on a hull which shows the point to which a boat sinks when it is properly trimmed
windward - towards the wind or on the side facing the wind
windward helm - when the boats natural tendency is to want to change course to windward
windward mark - The mark at the end of the windward leg of the racecourse