1.
emergency, contingency, crisis, wartime
A serious emergency or crisis, especially one involving military conflict, national security threats, or large-scale disasters. In political and legal contexts, it specifically refers to armed conflicts or situations requiring military response.
Usage
有事 is a formal word used primarily in political, military, and legal contexts. It implies a serious national-level crisis, especially armed conflict or war. The antonym 平時 means "peacetime" or "normal times."
The term 有事法制 (emergency legislation) is an important concept in Japanese politics, referring to laws that define how the government responds to military threats.