Glossary
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TermDefinition
- 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...
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