The word Adamanteun is misspelled against Adamantean, an adjective meaning "adamant; hard as adamant."
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Adamantean has vowels 'ea' together mispronounced as 'eu'
Word contains consecutive vowels 'EA' in between alphabets adamant & n is misspelled as 'EU'
Wrong Spelling:  adamant-eu-n 
Correct Spelling:  adamant-ea-n 
Check more misspelled words of Adamantean to spell it correct.