In ancient Egyptian religion, an ennead was a group of nine gods. The principal ennead was the Great Ennead of Heliopolis. This group included the gods Atum, Shu, Tefnut, Geb, Nut, Osiris, Isis, Seth, and Nephthys. These nine can be considered the embodiments of the basic elements of life as set forth in Egyptian creation myth: life, sky, earth, and so on.
The number nine, or three times three, also might indicate a “plural of plurals,” or, simply, many gods. But generally an ennead was a group of exactly nine.
In the Heliopolitan version of creation, Atum, who created himself and then the world, begot Shu and Shu’s sister Tefnut. These two represented the air and moisture, respectively. Shu and Tefnut gave rise to Geb (earth) and hissister Nut (sky). Geb and Nut, in turn, gave birth to the four other pairs of male and female gods who embodied the balanced forces of order and disorder and played direct roles in the created universe.