ABS: American Bureau of Shipping: A U.S.-based private classification, or standards setting society for merchant ships and other marine systems

Against the Sun: Anti-clockwise circular motion. Left-handed ropes are coiled against the sun

Azimuth compass: An instrument employed for ascertaining position of the sun with respect to magnetic north. The azimuth of an object is its bearing from the observer measured as an angle clockwise from true north

Baggywrinkle: Chafing gear made from old ropes.

Barratry: Any wrongful act knowingly done by the master to the detriment of the owner of either ship or cargo; done without knowledge or consent of owner .

Bitter end: The final inboard end of chain or line

Blue Ensign: May be flown by british merchant vessels whose officers and crew include a certain number of retired Royal Navy personnel or Royal Navy reservists, or are commanded by an officer of the Royal Navy Reserve in possession of a Government warrant.

Bobstay: Cable,chain or rod holding down the end of the bowsprit

Center of effort: The center of wind pressure on the sail plan

Drift: A vessel leeway

El Niño:A warm inshore current annually flowing south along the coast of Ecuador. About every seven to ten years it extends down the coast of Peru , where it has a devastating effect.

Fathom: Measurement of six feet. (approximately 2 metres)

Field Day: Time set aside for cleaning

Flying bridge: An added set of controls above the level of the normal control station for better visibility. Usually open, but may have a collapsible top for shade.

Fouled: Any piece of equipment that is jammed or entangled, or dirtied

Great Circle: Acourse plotted on the surface of the globe that is the shortest distance between two points

Heel: To tip to one side

Hypothermia: the loss of body heat -- is the greatest danger for anyone in the water. As the body loses its heat, body functions slow down. This can quickly lead to death.

IMO: The International Maritime Organisation. Based in London, the IMO is the UN agency that overseas all safety policy and legislation for maritime shipping.Working closely with national agencies such as the UK's MCA, the IMO develops the international law of the sea.

Inspection Port: A watertight covering, that may be removed so the interior of the hull can be inspected or water removed

ISPS: International Ship and Port Facility Security

Jackstay: A strong line, or a wire stay running fore and aft along the sides of a boat to which a safety harness can be attached

Kedge: To use an anchor to move a boat by hauling on the anchor rode; a basic anchor type

King spoke: Marked top spoke on a wheel when the rudder is centered

Knot: A speed of one nautical mile (6076 feet)per hour

League: measure of distance three miles in length

Log: A navigation instrument used to estimate a ship's speed ora record of courses or operation which is a legal requirement.

Lubber's line:A mark or permanent line on a compass indicating the direction forward; parallel to the keel when properly installed

MCA: The Maritime and Coastguard Agency: an agency of the UK Government with responsibility for three facets of UK waters. These are, co-ordination of the UK's search and rescue organisations, through HM Coastguard; Port and Flag operations in the UK; and developing and contributing to legislation and safety policy with the IMO.

OPITO: Offshore Petroleum Industry Training Organization, responsible for ensuring the quality and content of key safety and emergency training for the Oil and Gas industry

PFD: Personal Flotation Devices (PFD), better known as life jackets

Piracy: The act of taking a ship on the high seas from those that own it

Pitching: The movement of a ship, by which she plunges her head and after-part alternately into the hollow of the sea

Plimsoll line:Waterlines to show the level the water should reach when the ship is properly loaded

Prop walk: Sideways force created by the spinning of the propeller

Q flag:All yellow signal flag meaning "My vessel is healthy and I request free pratique" and used in customs passage situations.

Red Ensign (or "Red Duster"): the Civil Ensign of the UK which is permitted to be used on merchant ships registered in the UK.

Rode: The anchor line and/or chain

RYA: Royal Yachting Association: Organisation overseeing leisure training on boats in the UK

Sea Anchor: Any device used to reduce a boat's drift before the wind

STCW 95: Standards of Training, Certification and Watchkeeping, (1995 version), the international standard for all those working on board commercial vessels, and formalized as a convention for training by the IMO. Recognised across the world and endorsed in the UK by the MCA.

Underway: Vessel in motion, when not moored, at anchor, or aground

VHF: Very high frequency radio

White Ensign (or "St George's Ensign): The ensign flown on Royal Navy ships and at land bases operated by the navy. It is also flown bymembers of the Royal Yacht Squadronandships escorting the Queen.

Waterline length:The length of the boat at the waterline

Yawing:The motion of a ship when she deviates from to the right or left

Zenith:The point of the celestial sphere which is directly overhead

Zulu time: GMT- Greenwich Mean Time, also known as Universal Time