Definify.com
Webster 1913 Edition
Cataclysm
Cat′a-clysm
,Noun.
[L.
cataclysmos
, Gr. κατακλυσμός
, from [GREEK] to dash over, inundate; κατά
downward, against + [GREEK] to wash or dash over: cf. F. cataclysme
.] 1.
An extensive overflow or sweeping flood of water; a deluge.
2.
(Geol.)
Any violent catastrophe, involving sudden and extensive changes of the earth’s surface.