cataclysm (n.)youdaoicibaDictYouDict[cataclysm 词源字典]
1630s, from French cataclysme (16c.), from Latin cataclysmos or directly from Greek kataklysmos "deluge, flood, inundation," from kataklyzein "to deluge," from kata "down" (see cata-) + klyzein "to wash," from PIE *kleue- "to wash, clean" (see cloaca).[cataclysm etymology, cataclysm origin, 英语词源]