An equinox is when the Sun is exactly over the Earth's equator. This happens twice a year on or about the 21st of March and on or about the 21st of September. Both equinoxes have an equal number of light and dark hours all over the world in the North and South Hemispheres.

The equinoxes and the solstices, are celebrated in Neo-Paganism, Wicca and some Trads in Traditional British Witchcraft, as well as in some cultures and other Pagan religions.