A fairy (also fata, fay, fey, fae, fair folk from faery, faerie, "realm of the fays") is a type of mythical being or legendary creature in European folklore (and particularly Celtic, Slavic, German, English, and French folklore), a form of spirit, often described as metaphysical, supernatural, or preternatural. Myths and stories about fairies do not have a single origin, but are rather a collection of folk beliefs from disparate sources. Various folk theories about the origins of fairies include casting them as either demoted angels or demons in a Christian tradition, as minor deities in pre-Christian Pagan belief systems, as spirits of the dead, as prehistoric precursors to humans, or as elementals. The label of fairy has at times applied only to specific magical creatures with human appearance, small stature, magical powers, and a penchant for trickery. At other times it has been used to describe any magical creature, such as goblins and gnomes. Fairy has at times been used as an adjective, with a meaning equivalent to "enchanted" or "magical".