‘灾难’ (zāi nàn) is a compound noun meaning 'calamity' or 'catastrophe'—a sudden, large-scale event causing severe harm, loss, or suffering. The first character 灾 (zāi) means 'disaster' and often refers to natural or man-made destructive events like floods, fires, or epidemics; the second character 难 (nàn) means 'hardship' or 'distress', intensifying the sense of profound difficulty and suffering. Together, they emphasize both the external event and its devastating human impact.

This word is formal and serious, commonly used in news reports, official statements, historical accounts, and discussions about public safety or crisis response. It carries strong emotional weight and is rarely used lightly or humorously. While it can describe natural phenomena (e.g., earthquakes), it’s equally applied to social or health-related crises—such as pandemics or industrial accidents—where widespread harm occurs. Learners should avoid using it for minor inconveniences (e.g., spilling coffee), as that would sound exaggerated or inappropriate.