Saltire

A saltire, also called St Andrew's Cross, is a heraldic symbol in the form of a diagonal cross, like the shape of the letter X in Roman type. The word comes from the Middle French sautoir ("stirrup"), possibly owing to the shape of the triangular areas in the design.

It appears in numerous flags, including those of Scotland and Jamaica, and other coats of arms and seals. A variant, also appearing on many past and present flags and symbols, is the Cross of Burgundy flag.

A warning sign in the shape of a saltire is also used to indicate the point at which a railway line intersects a road at a level crossing.

In Unicode, the cross is encoded at U+2613 ☓ SALTIRE (HTML ☓). See X mark#Unicode for similar symbols that might be more accessible.

The saltire appears on vexilla that are represented consistently on coinage of Christian emperors of Rome, beginning in the fourth century. Anne Roes found it on coins of Constantius II, Valentinian, Jovian, Gratianus, Valens, Arcadius, Constantine III, Jovinus, Theodosius I, Eugenius and Theodosius II, though she searched only coins at the British Museum. In the ninth and tenth century the saltire was revived in Constantinople as a symbol of Christian-imperial power.

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