Mortmun or Mortmain: How To spell?
The word Mortmun is misspelled against Mortmain, a noun meaning "Possession of lands or tenements in, or conveyance to, dead hands, or hands that cannot alienate."
Word contains consecutive vowels 'AI' in between alphabets mortm & n is misspelled as 'U'Wrong Spelling:  mortm-u-n  Correct Spelling:  mortm-ai-n 
Check more misspelled words of Mortmain to spell it correct.