Source : Webster's Revised Unabridged Dictionary (1913)

Persism \Per"sism\, n.
   Ancient Persian religion, esp. as represented by the Magi.

         This system we shall call 'Persism', in order to free
         ourselves of the popular associations still connected
         with such terms as magism, Parseeism, and so forth;
         meaning by 'Persism' the teaching of Zarathustra as it
         affected the Greek and Latin world.      --E. Vernon
                                                  Arnold.

Persism \Per"sism\, n.
   A Persian idiom.