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.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.