Cataclysm

Noun

 * 1) A sudden, violent event.
 * 2)  A sudden and violent change in the earth's crust.
 * 3) A great flood.

Synonyms for Cataclysm
catastrophe, upheaval, disaster, flood, convulsion, misfortune, calamity.

Derived terms

 * cataclysmic

Related terms

 * catastrophe

Thesaurus
accident, alluvion, alluvium, apoplexy, bloodless revolution, blow, bouleversement, breakdown, breaking up, breakup, calamity, casualty, cataract, catastrophe, cave, cave-in, clean slate, clean sweep, climax, collapse, collision, computer revolution, contretemps, convulsion, counterrevolution, crack-up, crash, debacle, deluge, diastrophism, disaster, engulfment, fit, flood, flooding, grief, ill hap, inundation, misadventure, mischance, misfortune, mishap, nasty blow, overflow, overflowing, overrunning, overthrow, overturn, palace revolution, paroxysm, pileup, pour, quake, radical change, revolt, revolution, revolutionary war, revulsion, shipwreck, shock, smash, smashup, spasm, spate, spill, spillage, staggering blow, striking alteration, stroke, submersion, subversion, sweeping change, tabula rasa, technological revolution, temblor, the Deluge, the Flood, tidal wave, torrent, total change, total loss, tragedy, transilience, tsunami, upheaval, upset, violent change, washout, whelming, wrack, wreck

Etymology
cataclysme:, from Latinized Greek cataclysmos:, from κατακλυσμός:, from κατακλύζω:, from κατά: + κλύζω:.