ABAFT - Toward the rear (stern) of the boat. Behind.

ABEAM - At right angles to the keel of the boat, but not on the boat.

ABOARD - On or within the boat.

ADRIFT - Loose, not on moorings or towline.

AFT - Toward the stern of the boat.

AGROUND - Touching or fast to the bottom.

ANCHORAGE - A place suitable for anchoring in relation to the wind, seas and bottom.

ASTERN - In back of the boat, opposite of ahead.

B 

BEAM - The greatest width of the boat.

BEARING - The direction of an object expressed either as a true bearing as shown on the chart, or as a bearing relative to the heading of the boat.

BELOW - Beneath the deck.

BITTER END - The last part of a rope or chain.The inboard end of the anchor rode.

BOAT - A fairly indefinite term. A waterborne vehicle smaller than a ship. One definition is a small craft carried aboard a ship.

BOAT HOOK - A short shaft with a fitting at one end shaped to facilitate use in putting a line over a piling, recovering an object dropped overboard, or in pushing or fending off.

BOW - The forward part of a boat.

BOW LINE - A docking line leading from the bow.

BULKHEAD - A vertical partition separating compartments.

BUOY - An anchored float used for marking a position on the water or a hazard or a shoal and for mooring.

BURDENED VESSEL - That vessel which, according to the applicable Navigation Rules, must give way to the privileged vessel. The term has been superseded by the term "give-way".

C

CABIN - A compartment for passengers or crew.

CAPSIZE - To turn over.

CAST OFF - To let go.

CHOCK - A fitting through which anchor or mooring lines are led. Usually U-shaped to reduce chafe.

CLEAT - A fitting to which lines are made fast. The classic cleat to which lines are belayed is approximately anvil-shaped.

COCKPIT - An opening in the deck from which the boat is handled.

COURSE - The direction in which a boat is steered.

CURRENT - The horizontal movement of water.

D  

DEAD AHEAD - Directly ahead.

DEAD ASTERN - Directly aft.

DECK - A permanent covering over a compartment, hull or any part thereof.

DINGHY - A small open boat. A dinghy is often used as a tender for a larger craft.

DISPLACEMENT - The weight of water displaced by a floating vessel, thus, a boat's weight.

DISPLACEMENT HULL - A type of hull that plows through the water, displacing a weight of water equal to its own weight, even when more power is added.

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 water a boat draws.

E  

EBB - A receding current.

F  

FATHOM - Six feet.

FENDER - A cushion, placed between boats, or between a boat and a pier, to prevent damage.

FLARE - The outward curve of a vessel's sides near the bow. A distress signal.

FLOODTIDE - A incoming current.

FLOORBOARDS - The surface of the cockpit on which the crew stand.

FLUKE - The palm of an anchor.

FOLLOWING SEA - An overtaking sea that comes from astern.

FORWARD - Toward the bow of the boat.

FOULED - Any piece of equipment that is jammed or entangled, or dirtied.

G  

GALLEY - The kitchen area of a boat.

GANGWAY - The area of a ship's side where people board and disembark.

GROUND TACKLE - A collective term for the anchor and its associated gear.

GUNWALE - The upper edge of a boat's sides.

H  

HARD CHINE - An abrupt intersection between the hull side and the hull bottom of a boat so constructed.

HATCH - An opening in a boat's deck fitted with a watertight cover.

HEAD - A marine toilet. Also 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. Opposite of sternway.

HELM - The wheel or tiller controlling the rudder.

HELMSPERSON - The person who steers the boat.

HOLD - A compartment below deck in a large vessel, used solely for carrying cargo.

HULL - The main body of a vessel.

I  

INBOARD - More toward the center of a vessel; inside; a motor fitted inside a boat.

J  

JETTY - A structure, usually masonry, projecting out from the shore; a jetty may protect a harbor entrance.

K  

KEEL - The centerline of a boat running fore and aft; the backbone of a vessel.

KNOT - A measure of speed equal to one nautical mile (6076 feet) per hour.

A fastening made by interweaving rope to form a stopper, to enclose or bind an object, to form a loop or a noose, to tie a small rope to an object, or to tie the ends of two small ropes together.

L  

LATITUDE - The distance north or south of the equator measured and expressed in degrees.

LAZARETTE - A storage space in a boat's stern area.

LEEWARD - The direction away from the wind. Opposite of windward.

LINE - Rope and cordage used aboard a vessel.

LONGITUDE - The distance in degrees east or west of the meridian at Greenwich, England.

M  

MIDSHIP - Approximately in the location equally distant from the bow and stern.

MOORING - An arrangement for securing a boat to a mooring buoy or a pier.

N  

NAUTICAL MILE - One minute of latitude; approximately 6076 feet - about 1/8 longer than the statute mile of 5280 feet.

NAVIGATION - The art and science of conducting a boat safely from one point to another.

NAVIGATION RULES - The regulations governing the movement of vessels in relation to each other, generally called steering and sailing rules.

O  

OUTBOARD - Toward or beyond the boat's sides. A detachable engine mounted on a boat's stern.

OVERBOARD - Over the side or out of the boat.

P  

PIER - A loading platform extending at an angle from the shore.

PILE - A wood, metal or concrete pole driven into the bottom. Craft may be made fast to a pile; it may be used to support a pier (see PILING) or a float.

PLANING - A boat is said to be planing when it is essentially moving over the top of the water rather than through the water.

PLANING HULL - A type of hull shaped to glide easily across the water at high speed.

PORT - The left side of a boat looking forward. A harbor.

Q  

QUARTERING SEA - Sea coming on a boat's quarter.

R  

RODE - The anchor line and/or chain.

ROPE - In general, cordage as it is purchased at the store. When it comes aboard a vessel and is put to use it becomes line.

RUDDER - A vertical plate or board for steering a boat.

RUNNING LIGHTS - Lights required to be shown on boats underway between sundown and sunup.

S  

SCOPE - Technically, the ratio of length of anchor rode in use to the vertical distance from the bow of the vessel to the bottom of the water. Usually six to seven to one for calm weather and more scope in storm conditions.

SCREW - A boat's propeller.

SCUPPERS - Drain holes on deck, in the toe rail, or in bulwarks or (with drain pipes) in the deck itself.

SEA COCK - A through hull valve, a shut off on a plumbing or drain pipe between the vessel's interior and the sea.

SEAMANSHIP - All the arts and skills of boat handling, ranging from maintenence and repairs to piloting, sail handling, marlinespike work, and rigging.

SEAWORTHY - A boat or a boat's gear able to meet the usual sea conditions.

SECURE - To make fast.

SOUNDING - A measurement of the depth of water.

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.

SQUARE KNOT - A knot used to join two lines of similar size. Also called a reef knot.

STARBOARD - The right side of a boat when looking forward.

STERN - The after part of the boat.

STOW - To put an item in its proper place.

T  

TIDE - The periodic rise and fall of water level in the oceans.

TOPSIDES - The sides of a vessel between the waterline and the deck; sometimes referring to onto or above the deck.

TRANSOM - The stern cross-section of a square sterned boat.

TRIM - Fore and aft balance of a boat.

U  

UNDERWAY - Vessel in motion, i.e., when not moored, at anchor, or aground.

V  

V HULL - A hull with the bottom section in the shape of a "V".

W  

WAKE - Moving waves, track or path that a boat leaves behind it, when moving across the waters.

WATERLINE - A line painted on a hull which shows the point to which a boat sinks when it is properly trimmed (see BOOT TOP).

Y  

YACHT - A pleasure vessel, a pleasure boat; in American usage the idea of size and luxury is conveyed, either sail or power.