In Sumerian religion, Ninlil (DNIN.LÍL"lady of the open field" or "Lady of the Air"), also called Sud, in Assyrian called Mullitu, is the consort goddess of Enlil. Her parentage is variously described. Most commonly she is called the daughter of Haia (god of stores) and Nunbarsegunu (or Ninshebargunnu (a goddess of barley) or Nisaba). Another source says she is the daughter of Anu and Antu. Other sources call her a daughter of An and Nammu. Theophilus G. Pinches noted that Nnlil or Belit Ilani had seven different names (such as Nintud, Ninhursag, Ninmah, etc.) for seven different localities.
She lived in Dilmun with her family. Raped and ravaged by her (now-present) husband Enlil, who impregnated her with water, she conceived a boy, Nanna/Suen, the future moon god. As punishment Enlil was dispatched to the underworld kingdom of Ereshkigal, where Ninlil joined him. Enlil impregnated her disguised as the gatekeeper, whereupon she gave birth to their son Nergal, god of death. In a similar manner she conceived the underworld god Ninazu when Enlil impregnated her disguised as the man of the river of the nether world, a man-devouring river. Later Enlil disguised himself as the man of the boat, impregnating her with a fourth deity Enbilulu, god of rivers and canals, these act as substitutes for Nanna/Suen to ascend. In some texts Ninlil is also the mother of Ninurta.
After her death, she became the goddess of the air, like Enlil. She may be the Goddess of the South Wind referred to in the story of Adapa, as her husband Enlil was associated with northerly winter storms. As "Lady Air" she may be associated with the figure of the Akkadian demon "Lil-itu", thought to have been the origin of the Biblical Lilith.