反击 literally means 'reverse strike' — 反 (fǎn) means 'against' or 'in reverse', and 击 (jī) means 'to strike' or 'to attack'. Together, they form a compound meaning 'counterattack': an offensive action taken in response to an initial attack. It emphasizes immediacy, intentionality, and strategic defense turning into offense.

This word is used both literally and figuratively — in military contexts, sports (e.g., fencing or boxing), debates, business competition, and even animal behavior (e.g., prey defending itself). As a noun, it refers to the act or instance of counterattacking; as a verb, it describes the action itself ('to counterattack'). It carries a sense of resolve and tactical response rather than mere reaction.