Glossary
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TermDefinition
- General Nautical Terminology Ready AboutThe helmsman’s shout that he intends to go about shortly
- Flag Semaphore Ready (Flag Semaphore)

The Ready (Flag Semaphore) signal shows the sender is ready to send a message. The same shape is also used for Space (Flag Semaphore) & Rest...
More Details - Flag Semaphore Ready to Recieve (Flag Semaphore)

The Ready to Recieve signal shows the sender that the recipient is ready to receive a message. This shape is displayed once the sender has...
More Details - General Nautical Terminology Reef
A reef is a submerged ridge of rock, coral, or sand near the surface of oceans or seas. It can be made up of living organisms like coral or...
More Details - General Nautical Terminology Reefing
The act of reducing the area of a sail to decrease wind exposure and maintain control in strong winds.
Reefing is an essential technique in...
More Details - General Nautical Terminology Reefing Hook
A reefing hook is located near the bottom of the mast at the gooseneck, where the boom connects to the mast. When reefing, the cringle is placed...
More Details - General Nautical Terminology, Parts of a Boat Reefing Lines
Ropes or cords used to reduce the sail area by securing a portion of the sail to the boom or mast, thereby making the vessel more manageable in...
More Details - Flag Semaphore Rest (Flag Semaphore)

When the sender is not actively sending messages, both flags are held by their side. The same shape is also used for Space (Flag Semaphore) &...
More Details - Abbreviation, General Nautical Terminology Restricted in Ability to Manoeuvre (RAM)
A ship that, due to the nature of its work, is unable to keep out of the way of other vessels as required by the International Regulations for...
More Details - General Nautical Terminology Restricted Visibility
Conditions in which a vessel's ability to see is significantly reduced due to environmental factors such as fog, heavy rain, snow, or...
More Details - General Nautical Terminology Rhumb LineA line on the surface of the earth that cuts all meridians at the same angle. On a standard Mercator chart the rhumb line appears as a straight line
- General Nautical Terminology Riding Turn
A loop of rope that crosses over itself on a winch drum or cleat, often causing friction or jamming.
A riding turn is a term commonly used in...
More Details - General Nautical Terminology Rigging
The system of ropes, cables, chains, and other apparatus used to support and control the sails and masts of a sailing vessel.
Rigging is...
More Details - General Nautical Terminology Rigging
Verb - The process of setting up and adjusting the sails, lines, and other necessary equipment on a boat or ship to ensure it is ready for...
More Details - General Nautical Terminology Rigid Inflatable BoatA vessel that has both a solid part and inflatable part to its structure
- Organisation RINA
An internationally renowned professional institution representing naval architects and marine engineers worldwide. It was founded in 1860 and is...
More Details - General Nautical Terminology Risk of Collision
The possibility that a collision may occur, usually established by taking a compass bearing of an approaching vessel. Defined in Rule 7 - Risk of...
More Details - Flag Semaphore, Signals & Communication Letter R (Flag Semaphore)

Flag semaphore indicating the letter R.
- Morse Code, Signals & Communication Letter R (Morse Code)
International Morse Code sequence representing the letter R.
- Organisation RNLI
The volunteer crewed rescue service providing 24-hour rescue services around the UK and Irish coastline. They also provide seasonal lifeguards...
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