Glossary Archive

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 used the Attention (Flag Semaphore) signal before starting the communication.

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 formed by the accumulation of sand or rocks. Reefs are important ecosystems that provide habitat for various marine life and help protect coastlines from erosion.

Verb: Reefing refers to the act of reducing the area of a sail to decrease wind exposure and maintain control in strong winds. Noun: Reefing is the process or technique used to reduce the sail area by folding or rolling part of the sail and securing it to the boom or mast. Reefing is an...

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 over the reefing hook to secure the sail when reducing its area. This setup allows for easier and quicker reefing in strong winds, ensuring the sail is properly...

Reefing lines are used to reduce the size of the mainsail. By reducing the size of the mainsail we can improve the yacht's stability and performance as the wind increases

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) & Ready (Flag Semaphore).

Unable to get out of the way due to work being done. Could be a dredger, towing vessel etc.

Visibility restricted by rain, drizzle, fog, etc., during which vessels are required to proceed at a safe speed and to navigate with extreme caution

A 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

On a winch the situation where an earlier turn rides over a later turn and jams