Cataclysm
CATACLYSM , a great flood or deluge (q.v.). The term is used in geology to denote an overwhelming catastrophe which has produced sudden changes in the earth's surface; and also, figuratively, of any great and violent change which sweeps away the existing social or political order.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)
