1. a large-scale and violent event in the natural world: "the cataclysm at the end of the Cretaceous Period"
▪ a sudden violent upheaval, especially in a political or social context:"the cataclysm of the First World War"
Word Originearly 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’.
