The Collaborative International Dictionary of English v.0.48:

Cosmogony \Cos*mog"o*ny\ (-n?), n.; pl. Cosmogonies (-n?z).
   [Gr. kosmogoni`a; ko`smos the world + root of gi`gnesthai to
   be born: cf. F. cosmogonie.]
   The creation of the world or universe; a theory or account of
   such creation; as, the poetical cosmogony of Hesoid; the
   cosmogonies of Thales, Anaxagoras, and Plato.
   [1913 Webster]

         The cosmogony or creation of the world has puzzled
         philosophers of all ages.                --Goldsmith.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cosmogony
    n 1: the branch of astrophysics that studies the origin and
         evolution and structure of the universe [syn: cosmology,
         cosmogony, cosmogeny]