| process where the surface of the earth is worn away by the action of water, glaciers, winds, waves |
| outer layer of the earth, about 22 miles deep under the continents and 6 miles deep under the oceans |
catastrophe
in literature, the final action that completes the unraveling of the plot in a play, especially in a tragedy. Catastrophe is a synonym of denouement. The term is sometimes applied to a similar action in a novel or story.
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