Insesion or Insession: How To spell?
The word Insesion is misspelled against Insession, a noun meaning "That in which one sits, as a bathing tub."
Insession has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings inse & ion which should not be misspelled with single 'S'
Wrong Spelling:  inse-s-ion  Correct Spelling:  inse-ss-ion 
Find more incorrect spellings of Insession to spell right way.