Source : Webster's Revised Unabridged Dictionary (1913)

Theophany \The*oph"a*ny\, n.; pl. {-nies}. [Gr. ?; ? God + ? to
   appear.]
   A manifestation of God to man by actual appearance, usually
   as an incarnation.

Source : WordNet®

theophany
     n : a visible (but not necessarily material) manifestation of a
         deity to a human person