CATACLYSM

Cat″a‐clysm (?), n. [[L. cataclysmos, Gr. κατακλυσμόσ, from � to dash over, inundate; κατά downward, against + � to wash or dash over: cf. F. cataclysme.]] 1. 1. An extensive overflow or sweeping flood of water; a deluge.
2. 2. (Geol.) Any violent catastrophe, involving sudden and extensive changes of the earth's surface.