Source : Webster's Revised Unabridged Dictionary (1913)

Tempter \Tempt"er\, n.
   One who tempts or entices; especially, Satan, or the Devil,
   regarded as the great enticer to evil. ``Those who are bent
   to do wickedly will never want tempters to urge them on.''
   --Tillotson.

         So glozed the Tempter, and his proem tuned. --Milton.

Source : WordNet®

tempter
     n : a person who tempts others; "Satan is the great tempter of
         mankind"