halo

Radiance encircling the heads of saints and holy persons in art. It is also called an aureole, especially when surrounding the whole figure.

It may have originated in Egyptian art, where the Sun god Aton was shown with the disc of the Sun shining behind his head. There are also stories of Christian saints being transfigured with a shining face, similar to the transfiguration of Jesus.

The halo occurs in Hindu, oriental, and classical art, and has been used in the West as a symbol of sanctity from about the 5th century. As an attribute of power, it figures in Byzantine art in representations of Satan and other great powers of evil. Many Roman emperors are represented with radiating diadems or haloes.

The usual form of the nimbus is circular; sometimes it is formed by concentric circles, or indicated by a straight line or by rays diverging from the head. A triangular or cruciform halo marked one of the three persons of the Christian Trinity. A square nimbus denoted that the person represented was still living. The nimbus was usually of gold, but sometimes of other colours. After the Renaissance it became lighter, almost melting away into the picture. Haloes on statues may have their use as a protection from fouling by birds, especially when they lie flat on the head.