Cataclysm
Cataclysm , noun
[Latin cataclysmos, Greek kataklysmo`s, from {not transcribed} to dash over, inundate; kata` downward, against + {not transcribed} to wash or dash over: compare French cataclysme.]
1.
An extensive overflow or sweeping flood of water; a deluge.
2.
(Geology) Any violent catastrophe, involving sudden and extensive changes of the earth's surface.