Milennialist or Millennialist: How To spell?
The word Milennialist is misspelled against Millennialist, a noun meaning "One who believes that Christ will reign personally on earth a thousand years; a Chiliast; also, a believer in the universal prevalence of Christianity for a long period."
Millennialist has double "ll" is mispronounced as "l"Remember double 'LL' in between the strings mi & ennialist which should not be misspelled with single 'L'
Wrong Spelling:  mi-l-ennialist  Correct Spelling:  mi-ll-ennialist 
Find more wrongly spelled words of Millennialist to spell it well.