The Collaborative International Dictionary of English v.0.48:

Savior \Sav"ior\ (s[=a]v"y[~e]r), n. [OE. saveour, OF. salveor,
   F. sauveur, fr. L. salvator, fr. salvare to save. See Save,
   v.] [Written also saviour.]
   1. One who saves, preserves, or delivers from destruction or
      danger.
      [1913 Webster]

   2. Specifically: The (or our, your, etc.) Savior, he who
      brings salvation to men; Jesus Christ, the Redeemer.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Saviour
    n 1: a teacher and prophet born in Bethlehem and active in
         Nazareth; his life and sermons form the basis for
         Christianity (circa 4 BC - AD 29) [syn: Jesus, Jesus of
         Nazareth, the Nazarene, Jesus Christ, Christ,
         Savior, Saviour, Good Shepherd, Redeemer,
         Deliverer]
    2: a person who rescues you from harm or danger [syn: savior,
       saviour, rescuer, deliverer]