In Roman mythology, every man had a genius and every woman a juno (Juno was also the name for the queen of the gods).

Originally, the genius/juno were ancestors who guarded over their descendants. Over time, they turned into personal guardian spirits, granting intellect and prowess. Sacrifices were made to one's genius/juno on one's birthday.

The juno was worshipped under many titles:

• Iugalis - protected marriage
• Matronalis - protected married women
• Pronuba - protected the bride
• Virginalis - protected virginity

In addition to each genius/juno of individuals, regions, families, households and cities had a genius. The genius of the Roman race was a winged, naked youth. The genius dedicated to places were usually depicted as snakes.

See also Lares, Di Penates, Genius loci

In certain older translations of the Arabian Nights, a genius is a male jinni.