1911 Encyclopædia Britannica/Catastrophe

CATASTROPHE (Gr. καταστροφή, from καταστρέφειν, to overturn), a term of the ancient Greek drama for the change in the plot which leads up to the conclusion. The word is thus used of any sudden change, particularly of a violent or disastrous nature, and in geology of a cataclysm or great convulsion of the earth’s surface.