Catastrophe
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’).
wiktionary
From Ancient Greek καταστροφή(katastrophḗ), from καταστρέφω(katastréphō, “I overturn”), from κατά(katá, “down, against”) + στρέφω(stréphō, “I turn”).
etymonline
catastrophe (n.)
1530s, "reversal of what is expected" (especially a fatal turning point in a drama, the winding up of the plot), from Latin catastropha, from Greek katastrophe "an overturning; a sudden end," from katastrephein "to overturn, turn down, trample on; to come to an end," from kata "down" (see cata-) + strephein "turn" (from PIE root *streb(h)- "to wind, turn"). Extension to "sudden disaster" is first recorded 1748.
