Su (or Shu) was the primordial Egyptian air god and the first born of the creator sun-god Atum. He is one of the first nine deities in the Heliopolitan Theological System. He and his sister/consort Tefnut begot the next divine pair, Geb, the earth god, and Nut, the sky goddess. Su is frequently depicted as standing on the supine body holding Nut aloft in his raised arms. He can also be one of the several manifestations of the "eye of Re," and take the form of a lion, as can his sister. A.G.H.
Grimal, Pierre, Larousse World Mythology, Secaucus, New Jersey, Chartwell Books, 1965, p. 32
Jordan, Michael, Encyclopedia of Gods, New York, Facts On File, Inc. 1993, p. 243