Terreplen or Terreplein: How To spell?

The word Terreplen 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 'E' as letter 'I' is phonetically ignor
Wrong Spelling:  terrepl-e-n 
Correct Spelling:  terrepl-ei-n 
Explore spell check of Terreplein to spell without errors.