Millionaress or Millionairess: How To spell?

The word Millionaress is misspelled against Millionairess, a noun meaning "A woman who is a millionaire, or the wife of a millionaire."

Word contains consecutive vowels 'AI' in between alphabets million & ress is misspelled as 'A'
Wrong Spelling:  million-a-ress 
Correct Spelling:  million-ai-ress 
Find more incorrect spellings of Millionairess to spell right way.

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