Adition or Addition: How To spell?
The word Adition is misspelled against Addition, a noun meaning "A dot at the right side of a note as an indication that its sound is to be lengthened one half."
Addition has double "dd" is mispronounced as "d"Remember double 'DD' in between the strings A & ition which should not be misspelled with single 'D'
Wrong Spelling:  A-d-ition  Correct Spelling:  A-dd-ition 
Find more incorrect spellings of Addition to spell right way.