灾变 zāibiàn catastrophe Origin Definitions Defs Strokes Stroke Words Sentences Sents 灾变论 zāibiànlún catastrophism / convulsionism the theory that geological change is caused by sudden and violent events rather than gradual processes灾变说 zāibiànshuō catastrophism the geological theory that the Earth has been shaped by sudden, short-lived, violent events like the biblical flood