Signiorage or Seigniorage: How To spell?

The word Signiorage is misspelled against Seigniorage, a noun meaning "A share of the receipts of a business taken in payment for the use of a right, as a copyright or a patent."

Word contains consecutive vowels 'EI' in between alphabets s & gniorage is misspelled as 'I' as letter 'E' is phonetically igno
Wrong Spelling:  s-i-gniorage 
Correct Spelling:  s-ei-gniorage 
Find more incorrect spellings of Seigniorage to spell right way.