战役 (yìzhàn) is a noun meaning 'military campaign' — a large-scale, coordinated series of battles aimed at achieving a strategic objective, such as capturing territory or defeating an enemy force. The first character 战 (zhàn) means 'to fight' or 'battle', while 役 (yì) originally meant 'service' or 'duty', especially compulsory military service; together, they convey the idea of organized, purposeful combat operations over time and space.

Though rooted in military history, 战役 is also used metaphorically in modern Chinese for large-scale, goal-oriented efforts — for example, a 'poverty alleviation campaign' or a 'public health campaign'. It implies scale, planning, duration, and clear objectives, distinguishing it from smaller engagements like 战斗 (zhàndòu, 'skirmish') or single battles. It appears frequently in historical texts, news reports, and policy documents, and carries formal, often solemn connotations.