cataclysm
1. a sudden violent change in the earth's surface
2. an event resulting in great loss and misfortune

【例句】
- The eruption of the volcano was an unexpected cataclysm.
- The city has just experienced a cataclysmic flood.
- Then followed a comparatively long hiatus due to completely understandable causes resulting from the sociopolitical cataclysms.

【近义词】
- disaster 普通用词，指大破坏，灾难
- misfortune 普通用词，外在因素导致的不幸
- calamity 个人的不幸，更严重
- catastrophe 语气最强