cataclysm
noun
[ ˈkatəˌklɪz(ə)m ]
• a large-scale and violent event in the natural world.
• "the cataclysm at the end of the Cretaceous Period"
Origin:
early 17th century (originally denoting the biblical Flood described in Genesis): from French cataclysme, via Latin from Greek kataklusmos ‘deluge’, from kata- ‘down’ + kluzein ‘to wash’.
