Glossary
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TermDefinition
- General Nautical Terminology, Parts of a Boat Locker
A storage compartment or enclosed space on a boat, typically used for stowing equipment, gear, or provisions securely.
A locker on a boat is a...
More Details - General Nautical Terminology Logbook
An official record maintained aboard a vessel that documents the ship's daily activities, including navigational data, weather conditions, and...
More Details - General Nautical Terminology Log Line
A device used historically by mariners to measure a vessel's speed through the water.
The log line consists of a wooden board, known as the...
More Details - General Nautical Terminology Log ReadingThe reading of distance travelled through the water usually taken every hour from the log and recorded in the deck log
- General Nautical Terminology, Navigation Longitude
The geographic coordinate that specifies the east-west position of a point on the Earth's surface, measured in degrees(°), minutes(') and...
More Details - 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, Navigation Magnetic North
The direction towards the Earth's magnetic north pole, where a compass needle points, which differs from true geographic north.
Magnetic North...
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 Sail
Raising sail and getting under way using sail power.
This appears to be an unusual or possibly local expression, and may be intended to refer...
More Details - 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 Fast
Securing a rope, line or vessel so it remains held in place.
This is used when attaching mooring lines to cleats, bollards, rings, buoys or...
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