‘讨伐’ is a formal, literary verb meaning ‘to launch a punitive expedition’ — that is, to organize and lead a military or political campaign against someone or something deemed unjust, rebellious, or harmful. The character 讨 (tǎo) originally means ‘to investigate, demand, or punish’, while 伐 (fá) means ‘to attack, subdue, or conquer’. Together, they convey a sense of righteous, authorized action taken to correct wrongdoing or restore order — not mere aggression, but morally justified enforcement.

This term appears frequently in historical texts, official announcements, political rhetoric, and media commentary. It carries strong connotations of legitimacy, moral authority, and institutional backing — you would not use it for personal disputes or casual criticism. Though rooted in ancient warfare, modern usage extends metaphorically to campaigns against corruption, environmental violations, or ideological threats, always implying organized, principled opposition.