Prexistency or Preexistency: How To spell?
The word Prexistency is misspelled against Preexistency, a noun meaning "Preexistence."
Preexistency has double "ee" is mispronounced as "e"Remember double 'EE' in between the strings Pr & xistency which should not be misspelled with single 'E'
Wrong Spelling:  Pr-e-xistency  Correct Spelling:  Pr-ee-xistency 
Find more wrongly spelled words of Preexistency to spell it well.