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Swallowtail flag shape

Abarn swallow in flight. Note the shape of its tail

Inflag terminology, aswallowtail is either

1. a V-shaped cut in a flag that causes the flag to end in two points at the fly; or
2. any flag that has this V-shaped cut.

The name comes from the forked tail that is a common feature of theswallow species of birds.

Common in theNordic countries, this swallowtail flag contains a vertical section in the centre of the fly.

Also common in the Nordic countries, the swallowtail flag contains a third tail (the "tongue") between the other two tails.

The triangular swallowtail is the shape of the flag of the American state ofOhio,^[1] as well as of someburgees,private signals and pennants of theInternational Code of Signals (ICS).

A guidon is the general name given to a small swallowtail flag. Guidons are used to represent military units and are displayed on vehicles attached to a particular unit. In some countries (such as theUnited States), guidons do not necessarily have a swallow tail.

The military use of the guidon originated from the flags used bycavalry units in Europe. A variant of the guidon, thehussar cut, was used by German cavalry regiments. Instead of a straight V-shaped cut, the swallowtail in a hussar cut flag is curved.

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