Aether in Greek Aither, ("upper air"), in Greek mythology, was the personification of the "upper sky", space and heaven. He is the pure, upper air that the gods breathe, as opposed to "aer", which mortals breathed. He was the son of Erebus and Nyx, and brother of Hemera. He is the soul of the world and all life emanates from him. The aether was also known as Zeus defensive wall; the bound that locked Tartaros from the cosmos.
"I swear by holly aither, home of Zeus". Zeus is called Zeus aitherios
and Aeschylus :
Zeus is the aither, Zeus the earth, and Zeus the sky,
Zeus the whole world and aught there is above it.