‘挡箭牌’ literally means 'arrow-blocking board' — a shield historically used to protect soldiers from enemy arrows. Figuratively, it refers to a person or thing used to absorb blame, criticism, or danger on behalf of someone else — essentially a scapegoat or human shield. The character 挡 means 'to block or ward off', 箭 means 'arrow', and 牌 means 'board' or 'plaque'; together, they evoke the image of a physical barrier repelling harm, extended metaphorically to social or political protection.

This term is commonly used in informal and semi-formal contexts — especially when discussing office politics, family conflicts, or public relations — where someone is deliberately positioned to deflect responsibility. It carries a slightly negative, cynical connotation, implying manipulation or unfair burden-shifting. While rooted in ancient warfare imagery, it’s rarely used in literal military descriptions today; its power lies entirely in its figurative resonance.