The Collaborative International Dictionary of English v.0.48:

Parsiism \Parsiism\ (p[aum]r"s[=e]*[i^]z'm or
   p[aum]r*s[=e]"[i^]z'm) prop. n.
   1. Same as Parseeism.

   Syn: Parseeism.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Parsiism
    n 1: the faith of a Zoroastrian sect in India [syn: Parsiism,
         Parseeism]