Glossary Archive

The depth of water below chart datum

A waterproof oilskin hat with a broad brim

This shape indicates a space, usually between words. The same shape is also used for Rest (Flag Semaphore) & Ready (Flag Semaphore).

Any long, sturdy pole or beam used on a ship to support sails, rigging, or other equipment. Spars are typically made of wood, metal, or composite materials and are essential to a ship’s rigging system. There are several types of spars on a vessel, each serving different functions in relation to the sails and mast....

The speed made good over the ground; that is , the boat speed corrected for tidal stream and leeway

The actual speed your vessel is tracking over the seabed

To ease the sheets so that the sail is only partly filled by the wind, the rest being spilt

A large, lightweight, and often colourful sail designed for use when sailing downwind, typically set forward of the mainsail to maximise speed and efficiency. A spinnaker is a specialised sail used on sailing vessels to take advantage of wind coming from behind the boat, known as downwind sailing. It is distinct from other sails due...

A spar which is used to hold the spinnaker out

A projecting shoal or strip of land connected to the shore