n.（突然降临的）大灾难
The extinct volcano's eruption would mean a cataclysm for the city.
死火山又重新喷发,对这座城市来说意味着大难临头.
The floods were a cataclysm from which the local people never recovered.
经历了这场特大洪水,当地人民元气大伤,很难恢复.
The cataclysm flooded the entire valley.
洪水淹没了整个山谷.