A primeval Sumero-Akkadian god who personifies the primordial abyss of sweet waters underneath the earth. He is the consort of Tiamat, the primordial abyss of salt waters of Chaos. In the later mythology of the Enuma Elish, the sweet water mingled with the bitter waters of the sea and with a third watery element, perhaps cloud, the first gods were engendered. The waters of Apsu were thought of as held immobile underground by the 'spell' of Ea in a death-like sleep, but it is also said that Ea had Apsu fall asleep and had killed him. From the clay of Apsu man was fashioned. This appears to be a Sumerian myth, because in the Enuma Elish, Kingu's blood serves this purpose. Apsu's vizir, Mummu, was imprisioned in a house built on his body.