1) The double lion god, gaurdian of the sunrise and sunset. Between the lions is the akhet symbol which representthe horizon on which the sunrises or sets. This symbol is made up of a solar disk cradled between the two peaks of the mountain djew. The western peak was called Manu, while the eastern peak was called Bakhu. It was these peaks that supported the sky.
 

2) The Egyptian personification of the earth and god of the dead. He rules over the meeting point between the eastern and western horizons in the underworld. He is also the guardian of the gate through which the pharaoh passes into the underworld. Aker provides a safe passage for the barque of the sun during its nightly journey through the underworld. He is represented as a small strip of land with both ends forming the head of a lion or a human. Alternatively, he is also represented as a pair of lions with the back to each other, with one head facing the east and the other head facing the west, thus seeing the sun rise and set.
 

3) Aker was an ancient earth-god in Egypt. He was believed to guard the gates of the dawn from which the sun rose each morning. He was portrayed as a double-headed lion, or a two lions sitting back-to-back. Inbetween them is shown the sun with the sky overhead. In this way they form the akhet symbol, which was a symbol of the horizon. Occasionally they were portrayed bearing the akhet on their backs. The two lions were called Sef and Duau, which means "Yesterday" and "Today" respectively.

As Egyptians believed that the gates of the morning and evening were guarded by Aker, they often placed statues of lions at the doors of their palaces and tombs. This was to guard the households and tombs from evil spirits and other malevalent beings. Sometimes they gave these statues the heads of men and women. The Greeks called this class of statuary, "Sphinxes."

It is believed that Aker is probably a more ancient earth god than the Heliopolitan god, Geb.