Misis or Missis: How To spell?
The word Misis is misspelled against Missis, a noun meaning "A mistress; a wife; -- so used by the illiterate."
Missis has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings mi & is which should not be misspelled with single 'S'
Wrong Spelling:  mi-s-is  Correct Spelling:  mi-ss-is 
Find more wrongly spelled words of Missis to spell it well.