‘戒严’ (jiè yán) literally combines ‘戒’ (jiè), meaning ‘to guard against’, ‘to be on alert’, or ‘to forbid’, and ‘严’ (yán), meaning ‘strict’, ‘severe’, or ‘rigorous’. Together, they form a formal, official term for the temporary suspension of normal civil authority and the imposition of military control over civilian functions—what English calls ‘martial law’. It is typically declared during extreme emergencies such as armed uprisings, large-scale riots, natural disasters with collapsed governance, or wartime threats to national security.

This term carries strong political and legal weight in Chinese contexts. It implies extraordinary measures: curfews, restrictions on movement and assembly, censorship, and direct command by military authorities. While historically used in various countries, in modern China it is an exceptional constitutional measure governed by the National Defense Mobilization Law and rarely invoked—last formally applied nationwide in 1989. Its usage is almost exclusively in official, news, historical, or legal discourse—not in everyday conversation.