Glossary Archive

A maritime communication system that automatically transmits and receives vessel information such as position, speed, and course to enhance navigational safety. The Automatic Identification System (AIS) is a critical technology used in maritime navigation to improve safety and collision avoidance. It operates through the automatic exchange of data between vessels, shore stations, and other AIS-equipped...

The side of a vessel that is sheltered from the wind, also known as the leeward side. Alee is a nautical term used to describe the side of a ship or boat that is away from the wind or downwind. In sailing, wind direction plays a crucial role in determining how a vessel moves and...

This shape represents the Letter A (Flag Semaphore) and the Number 1 (Flag Semaphore). The presumed signals are letters. The signaller must use the 'Numerals (Numbers to Follow)' signal to indicate the next signal should be interpreted as a number. The signaller uses the Letter J (Flag Semaphore)--Letters to Follow--to revert to letters.

International Morse Code sequence representing the letter A.

All at sea is a nautical term for a situation where a ship or boat is adrift or lost at sea without any clear direction or sense of location.

A position above the deck, typically in the rigging or on the masts of a ship. Aloft is used to describe any position above a vessel's deck, particularly in relation to the masts, rigging, or sails. When sailors go aloft, they climb up into the rigging or onto the masts to perform tasks such as...

The position or location next to a vessel, dock, or quay where a ship can be moored or secured.  The term alongside is a fundamental concept in maritime operations, referring to the act or state of positioning a vessel parallel to another structure or vessel. When a ship comes alongside, it is manoeuvred carefully to...

Aloof originally had a different meaning than its modern-day use to describe someone emotionally distant. In maritime language, Aloof comes from the Middle English phrase “a luff,” where “luff” refers to the act of steering a ship’s bow into the wind (closer to the wind). The term describes keeping a boat at a distance or...

Pronounced: AL-far Letter "A" in the phonetic alphabet system.

Pronounced: AL-far Letter "A" in the phonetic alphabet system.