catastrophe
Pronunciation: /kəˈtastrəfi/
noun

Origin:
mid 16th century (in the sense 'denouement'): from Latin catastropha, from Greek katastrophē 'overturning, sudden turn', from kata- 'down' + strophē 'turning' (from strephein 'to turn')

Spelling help
Remember that the end of catastrophe is spelled -ophe.