Cataclysm

n.	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.

Noun	1.	cataclysm - a sudden violent change in the earth's surface Synonyms: catastrophe
	2.	cataclysm - an event resulting in great loss and misfortune; "the whole city was affected by the irremediable calamity"; "the earthquake was a disaster" Synonyms: calamity, catastrophe, tragedy, disaster

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