Sailing terms and nautical glossary
Find clear definitions of sailing terms, boat parts, knots, navigation and nautical abbreviations. New to sailing? Start with the everyday words below, then explore the full glossary by subject or search for a term.
Sailing terms for beginners
Begin with port and starboard, bow, windward and leeward. Learn how sheets and halyards control sails, then explore points of sail, tacking and gybing.
For terms in context, read our beginner sailing vocabulary guide. Ready to practise on the water? Our first sailing course guide explains how to choose a starting route.
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TermDefinition
- General Nautical Terminology, Nautical Topics, Parts of a Boat Dodger
A raised screen or fabric cover that shelters a cockpit or companionway from wind and spray.
On many sailing yachts, a dodger consists of a...
More Details - General Nautical Terminology, Nautical Topics, Navigation, Weather (Meteorology) Dogger
A named sea area used in the UK Shipping Forecast, centred on Dogger Bank in the North Sea.
The area lies between the United Kingdom and...
More Details - General Nautical Terminology, Nautical Topics, Maritime Language & Traditions, Organisation Dog Watch
One of two shortened two-hour watches traditionally scheduled from 16:00–18:00 and 18:00–20:00.
Splitting the normal four-hour period creates...
More Details - General Nautical Terminology, Nautical Topics, Mooring & Berthing, Navigation Dolphin
An isolated marine structure used for mooring, berthing guidance or protection.
A dolphin may be formed from a group of piles, a rigid column...
More Details - General Nautical Terminology, Nautical Topics, Navigation, Signals & Communication DOP
A dimensionless factor describing how satellite geometry amplifies ranging and timing errors in a GNSS position or time solution.
Satellites...
More Details - General Nautical Terminology, Knot, Nautical Topics, Mooring & Berthing Double Sheet Bend
A bend joining two ropes with an additional turn around the bight compared with a single sheet bend.
The extra turn can improve grip when...
More Details - General Nautical Terminology, Nautical Topics, Mooring & Berthing, Safety Double Up
To add mooring lines or duplicate selected leads to increase security or redundancy.
A vessel may double up before strong wind, heavy wash, a...
More Details - General Nautical Terminology, Nautical Topics, Parts of a Boat, Points of Sail, Safety Douse
To lower or take in a sail, or in another context to extinguish a light or flame.
Dousing a sail means removing its driving effect and...
More Details - General Nautical Terminology, Nautical Topics, Navigation, Weather (Meteorology) Dover
A named sea area used in the UK Shipping Forecast, covering the Strait of Dover and adjoining eastern English Channel.
The area lies between...
More Details - General Nautical Terminology, Nautical Topics, Depths & Clearance, Safety Downflooding
The entry of water into normally dry spaces through openings as a vessel heels or is immersed.
Open hatches, vents, doors and damaged closures...
More Details - General Nautical Terminology, Nautical Topics, Depths & Clearance, Safety Downflooding Angle
The angle of heel at which water can first enter a normally dry space through a relevant opening.
It limits the usable stability range even if...
More Details - General Nautical Terminology, Nautical Topics, Parts of a Boat, Points of Sail Downhaul
A line or tackle used to pull a sail, spar or fitting downwards or towards a lower control point.
Its function depends on the rig. A mainsail...
More Details - General Nautical Terminology, Nautical Topics, Depths & Clearance, Navigation Downstream
In the direction that a river or other watercourse normally flows.
Downstream is generally towards the lower reaches or mouth, while upstream...
More Details - General Nautical Terminology, Nautical Topics, Navigation, Points of Sail, Weather (Meteorology) Downwind
In or towards the direction to which the wind is blowing.
A position downwind lies on the lee side of the reference point. A vessel travelling...
More Details - General Nautical Terminology, Nautical Topics, Navigation DR
Estimating a vessel’s position by advancing a known position using course steered, speed through the water and elapsed time.
A dead-reckoning...
More Details - General Nautical Terminology, Nautical Topics, Mooring & Berthing, Safety Drag
To move across the seabed because an anchor is no longer holding the vessel securely.
An anchor may drag because it has not set, the holding...
More Details - General Nautical Terminology, Nautical Topics, Depths & Clearance, Navigation, Parts of a Boat Draught
The vertical distance from a vessel’s waterline to its lowest immersed point.
Also spelled “draft” in American English, draught may be...
More Details - General Nautical Terminology, Nautical Topics, Navigation, Safety Dredger
A vessel or floating plant equipped to excavate or remove material from the seabed.
Dredgers deepen or maintain channels and berths, recover...
More Details - General Nautical Terminology, Nautical Topics, Parts of a Boat Dressing a Knot
The process of arranging a knot's parts neatly in their intended positions before it is fully tightened.
Correct dressing removes unintended...
More Details - Abbreviation, General Nautical Terminology, Nautical Topics, Depths & Clearance, Navigation Dries (dr)
A feature that is covered at higher water but exposed at lower water.
A drying height is measured above chart datum and may be accompanied by dr.







