Glossary
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TermDefinition
- General Nautical Terminology, Nautical Saying In Stays
The moment when a sailing vessel is head-to-wind during a tack, temporarily losing forward momentum.
When a sailing vessel is "in stays," it...
More Details - Courses, RYA Intermediate WindsurfingThe RYA Intermediate Windsurfing course bridges the gap between beginner and advanced skills. Participants learn techniques for improving speed,... More Details
- Courses, RYA Intermediate Windsurfing (Planing)The RYA Intermediate Windsurfing (Planing) course introduces participants to planing techniques, enabling them to harness the power of stronger... More Details
- General Nautical Terminology, Organisation International Association of Lighthouse Authorities (IALA)
A non-governmental organisation that develops standards and best practices for the safety and efficiency of maritime navigation through the use...
More Details - General Nautical Terminology International Certificate of Competence (ICC)
An official document that certifies a person's ability to operate a pleasure craft in countries that recognise it.
The International...
More Details - Flag / Pennant, General Nautical Terminology, Signals & Communication International Code of Signals (ICS)
A system of flags, codes, and symbols used by ships to communicate essential messages and ensure safety at sea, regardless of language...
More Details - General Nautical Terminology International Convention for the Prevention of Pollution from Ships (MARPOL)
Established by the IMO, MARPOL is the convention for preventing pollution from ships. It is the main international convention covering the...
More Details - Did you know?, General Nautical Terminology, Navigation International Date Line (IDL)
An imaginary longitudinal line located at approximately 180 degrees longitude serving as the demarcation where the calendar date changes by one...
More Details - General Nautical Terminology, Navigation International Hydrographic Organization (IHO)
An intergovernmental organisation dedicated to ensuring the uniformity and standardisation of hydrographic and nautical charting practices...
More Details - Organisation International Maritime Organisation (IMO)
A specialised agency of the United Nations headquartered in London and responsible for regulating shipping, the IMO has 175 Member States.
The...
More Details - General Nautical Terminology, Organisation, Safety International Maritime Satellite Organisation (INMARSAT)
A global satellite communications organisation providing maritime, aviation, and land-based services for safety and operational...
More Details - Flag / Pennant, Signals & Communication International Maritime Signal Flags
A system of flags ships use to communicate messages, signals, or important information visually. Flags often represent letters, numbers, or...
More Details - Did you know?, Navigation International Meridian Conference
A diplomatic meeting held in 1884 in Washington, D.C., where representatives from 25 nations convened to establish a standard prime meridian for...
More Details - Morse Code, Signals & Communication International Morse Code
A standardised system of encoding text characters as sequences of dots (short signals) and dashes (long signals) used for communication,...
More Details - General Nautical Terminology International Regulations for Preventing Collisions at Sea (IRPCS)
- Organisation, Signals & Communication International Telecommunication Union (ITU)
A specialised agency of the United Nations responsible for coordinating global telecommunication operations and services, including radio...
More Details - General Nautical Terminology, Weather (Meteorology) Irish Sea
Sea area of the Met Office Shipping Forecast. Covers the Irish Sea between Ireland and Great Britain.
Between Ireland and Great Britain, the...
More Details - General Nautical Terminology IRPCS
- Organisation ISAF
World Sailing, formerly known as the International Sailing Federation (ISAF), is the governing body for the sport of sailing...
More Details - Light Characteristic Iso
A light where the duration of light and darkness are equal.
Isophase describes a navigational aid that emits a light signal with equal periods...
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