Glossary
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TermDefinition
- General Nautical Terminology, Safety Look-out
A crew member assigned to maintain a continuous watch for potential hazards, other vessels, or navigational markers while at sea.
A look-out...
More Details - General Nautical Terminology, Navigation LOP
Navigational lines drawn on a chart, each representing a possible location of a vessel based on a single observation or measurement.
A line...
More Details - General Nautical Terminology Lose WayA vessel loses way when she slows down and stops in the water
- General Nautical Terminology, Navigation Lowest Astronomical Tide (LAT)
The lowest level that sea tides can reach under normal meteorological conditions, based on astronomical influences such as the gravitational pull...
More Details - General Nautical Terminology Lubber LineThe marker in the compass which is aligned with the fore-and-aft line of the boat against which the course can be read off on the compass card
- General Nautical Terminology Luff
The leading edge, which is the part of the sail that faces the wind when the sail is set correctly.
The luff of a sail is a critical part of...
More Details - General Nautical Terminology Luff Up
To steer a sailing vessel closer to the wind, reducing the angle between the boat's heading and the direction of the wind.
"Luff up" is a...
More Details - General Nautical Terminology LullA temporary drop in wind speed
- General Nautical Terminology, Weather (Meteorology) Lundy
Sea area of the Met Office Shipping Forecast. Lies in the Bristol Channel, around Lundy Island off southwest England.
Named for Lundy Island...
More Details - General Nautical Terminology Magnetic North
Magnetic North refers to the direction indicated by a magnetic compass, which points towards the Earth’s magnetic north pole. This differs from...
More Details - Organisation MAIB
A UK government agency responsible for investigating marine accidents and incidents to improve maritime safety. Part of the Department for...
More Details - General Nautical Terminology Mail SailTo hoist the sails and get under way
- General Nautical Terminology Mainsail
The principal and typically largest sail on a sailing vessel, attached to the mainmast and used to harness wind power for propulsion.
The...
More Details - General Nautical Terminology Mainsheet Traveller
The mainsheet traveller is a system on a sailboat that allows for adjustment of the mainsheet attachment point along a track that runs across the...
More Details - General Nautical Terminology Make FastTo secure the vessel with mooring lines to the jetty or to tie up to a buoy
- General Nautical Terminology Making Way
A vessel that is moving through the water under its own power, whether by engine, sail, or other means.
A vessel is said to be "making way"...
More Details - General Nautical Terminology, Weather (Meteorology) Malin
Sea area of the Met Office Shipping Forecast. Located off the north coast of Ireland, near Malin Head.
After Malin Head, Ireland’s northernmost...
More Details - General Nautical Terminology, Safety Man Overboard
A situation where a person has fallen from a vessel into the water, requiring immediate rescue actions.
A man overboard situation is one of...
More Details - General Nautical Terminology Marina
A specially designed harbour or dock where boats and yachts are moored, often offering services such as refuelling, repairs, and...
More Details - Organisation Marine Accident and Investigation Branch (MAIB)
A UK government agency responsible for investigating marine accidents and incidents to improve maritime safety. Part of the Department for...
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