(p1. of genius) Protective spirits who guide human beings. In Etruscan and Roman art they were represented as naked winged youths. Since the seventeeth century the term has been applied to male and female winged figures; and, in the art of the ancient east, to hybrid beings with the heads of birds who appear in a posture of greeting or who are fertilizing the sacred tree, e.g. on Assyrian relief tablets and, similarly, on Cretan cameos (see illustration). Today, the term denotes ghostly beings endowed with supernatural powers.