The word Clustra is misspelled against Claustra, which is plural of "Claustrum"
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Word contains consecutive vowels 'AU' in between alphabets cl & stra is misspelled as 'U' as letter 'A' is phonetically ignored
Wrong Spelling:  cl-u-stra 
Correct Spelling:  cl-au-stra 
Check more misspelled words of Claustra to spell it correct.