1. A great, often sudden calamity.
2. A complete failure; a fiasco: The food was cold, the guests quarreled—the whole dinner was a catastrophe.
3. The concluding action of a drama, especially a classical tragedy, following the climax and containing a resolution of the plot.
4. A sudden violent change in the earth's surface; a cataclysm.
[Greek katastrophē, an overturning, ruin, conclusion, from katastrephein, to ruin, undo : kata-, cata- + strephein, to turn; see streb(h)- in the Appendix of Indo-European roots.]
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