Dismisal or Dismissal: How To spell?
The word Dismisal is misspelled against Dismissal, a noun meaning "Dismission; discharge."
Dismissal has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings dismi & al which should not be misspelled with single 'S'
Wrong Spelling:  dismi-s-al  Correct Spelling:  dismi-ss-al 
Find more wrongly spelled words of Dismissal to spell it well.