Reun or Rein: How To spell?

The word Reun is misspelled against Rein, meaning "A step attached to the bit for controlling a horse or other draft-animal."

Word contains consecutive vowels 'EI' in between alphabets r & n is misspelled as 'EU'
Wrong Spelling:  r-eu-n 
Correct Spelling:  r-ei-n 
Check more misspelled words of Rein to spell it correct.