Sevententh or Seventeenth: How To spell?
The word Sevententh is misspelled against Seventeenth, a noun meaning "An interval of two octaves and a third."
Seventeenth has double "ee" is mispronounced as "e"Remember double 'EE' in between the strings Sevent & nth which should not be misspelled with single 'E'
Wrong Spelling:  Sevent-e-nth  Correct Spelling:  Sevent-ee-nth 
Explore spell check of Seventeenth to spell without errors.