激慨 (jī kǎi) is a formal literary noun meaning 'intense indignation' — a deep, morally charged anger aroused by injustice, cruelty, or betrayal. It combines 激 (jī), meaning 'intense, stirring, agitated', and 慨 (kǎi), meaning 'to sigh with emotion; heartfelt feeling', especially sorrow or righteous anger. Together, they evoke a powerful, almost visceral emotional response rooted in moral conviction rather than personal grievance.

This word appears most often in written Chinese — essays, historical accounts, political commentary, or solemn speeches — where it conveys elevated, principled outrage. It is rarely used in casual speech; native speakers typically choose simpler terms like 愤怒 (fènnù, 'anger') or 气愤 (qìfèn, 'indignation') in everyday contexts. 激慨 carries weight and gravity, suggesting the speaker or writer is moved not just by emotion but by ethical duty.