The word Sweetheirt is misspelled against Sweetheart, a noun meaning "A lover of mistress."
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Sweetheart has vowels 'ea' together mispronounced as 'ei'
Word contains consecutive vowels 'EA' in between alphabets sweeth & rt is misspelled as 'EI'
Wrong Spelling:  sweeth-ei-rt 
Correct Spelling:  sweeth-ea-rt 
Find more wrongly spelled words of Sweetheart to spell it well.