The size of British Ensigns, Standards and Union flags are expressed in terms of breadths - a breadth being 23cm (traditionally and approximately 9 inches).
In Union Jacks and White, Blue and Red Ensigns, the length is twice the breadth. In Admiral's Flags and Commodore's Broad Pennants the length is one and a half times the breadth.
For example a 12 breadth White Ensign is 274cm (12 x 23) wide (breadth or width) and 552cm long. A 6 breadth Admiral's Flag is 138cm (6 x 23) wide and 207cm long.
The length of flags used at sea is generally twice the breadth. However, the standard shape on land, and as used by military authorities, is 3:5.
|Badge||A distinctive emblem that can be added to a flag.|
|Bicolour||A flag divided into two colours.|
The vertical dimension of a flag, or the unit of measuring such, as used by the Royal Navy.
One Breadth is 23cm.
|Broad Pennant||A short triangular flag with a swallow tail.|
|Burgee||A small triangular or tapered flag, sometimes swallow tailed, usually identifying a yacht club.|
|Canton||One quarter of a flag, usually the upper hoist quarter of the flag.|
|Colour||A military flag, originally used to indicate a regiment's position in a battle, but today reserved for ceremonial occasions. Normally made of silk and heavily embroidered.|
|Courtesy Flag||The naval or civil ensign of the host country flown by the visiting ship, see also Royal Navy Queen's Regulations.|
|Cross||The normal cross is of two equal arms crossing at their centre and extending to the edge of the flag.|
|Dexter||On the right-hand side of a shield to the observer's or spectator's left.|
|Emblem||A symbol, badge or device including a coat of arms.|
|Ensign||The flag flown at the stern of a ship, also used by Government departments and the Royal Air Force.|
|Field||The background colour of a flag or shield.|
|Fimbriation||A narrow band of colour separating two others.|
|Fly||The half of a flag away from the flagstaff.|
|Guidon||A military flag used for mounted troops on ceremonial occasions. Normally made of silk and heavily embroidered.|
|Halyard||The rope or cord onto which the flag is attached.|
|Heading||The part of the flag through which the cord runs. This is normally made of white fabric.|
|Headstick||A plastic fitting sewn in to the top of flags worn on Ensign or Jack staffs, that allows the Inglefield Clip to be repositioned. This permits the head of the flag to touch the truckhead or pulley block.|
|Hoist||The half of the flag nearest the staff; or raise several flags together.|
|Inglefield Clip||Metal quick release either plain or swivel, for attaching a flag to the hoist ropes. Used by the Royal Navy and the Royal Air Force. There are two types: a simple fixed clip and a swivel clip which allows the rope to rotate.|
|Jack||A flag flown at the bows of a ship to show nationality.|
|Length||The horizontal dimension of a flag.|
|National Flag||The flag indicating nationality used by a recognised nation or state.|
|Naval Ensign||A form or type of National flag used by naval vessels, and also used by naval establishments on land.|
|Obverse||The view of the flag which bears the principal design, or view of a flag with the staff on the observer's left.|
|Pall||A heraldic device like a letter Y, e.g. Flag National South Africa or Archbishop of Canterbury Primate of All England.|
|Pennant||A tapering flag at the masthead of a ship in commission, also used to show rank or signalling.|
|Pendant||Former synonym of pennant and pronounced the same way.|
|Pennon||A long flag, often tapering and divided at the end. A small triangular flag borne on a ship or boat.|
|Reverse||The opposite to obverse.|
|Saltire||A diagonal cross, into four compartments, St Andrew's cross and the flag of Scotland.|
|Sinister||Opposite of Dexter.|
|Slides||Small metal clips attached to the heading of a flag that fit into a track on the staff and keep the flag heading close to the staff. The tracks are normally only fitted on Jack and Ensign Staffs.|
|Staff||The pole from which a flag is flown e.g. Jack and Ensign Staff.|
|Standard||A heraldic flag with badges and labels e.g. The Royal Standard and flags for members of the Royal Family, ceremonial flag used by mounted troops and air force squadrons.|
|Toggle||Wooden fastening which passes through the eye of a looped rope, used by the Army.|
|Tricolour||A flag of three different colours, usually in equal areas.|
|Width||The vertical dimension of a flag.|
Shades of Naval Bunting and NATO stock numbers