Terreplyen or Terreplein: How To spell?

The word Terreplyen is misspelled against Terreplein, a noun meaning "The top, platform, or horizontal surface, of a rampart, on which the cannon are placed. See Illust. of Casemate."

Word contains consecutive vowels 'EI' in between alphabets terrepl & n is misspelled as 'YE'
Wrong Spelling:  terrepl-ye-n 
Correct Spelling:  terrepl-ei-n 
Explore spell check of Terreplein to spell without errors.