n. 1. A violent upheaval that causes great destruction or brings about a fundamental change. 2. A violent and sudden change in the earth's crust. 3. A devastating flood. [French cataclysme, from Latin cataclysmos, deluge, from Greek kataklusmos, from katakluzein, to inundate : kata-, intensive pref.; see CATA- + kluzein, to wash away.] cat′a·clysmic (-klĭzmĭk), cat′a·clysmal (-klĭzməl) adj. cat′a·clysmi·cal·ly adv. |
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