The Collaborative International Dictionary of English v.0.48:

Ramayana \Ra*ma"ya*na\ (r[aum]*m[aum]"y[.a]*n[.a]), n. [Skr.
   R[=a]m[=a]ya[.n]a.]
   The more ancient of the two great epic poems in Sanskrit. The
   hero and heroine are Rama and his wife Sita.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Ramayana
    n 1: one of two classical Hindu epics telling of the banishment
         of Rama from his kingdom and the abduction of his wife by a
         demon and Rama's restoration to the throne