knock-me-down

An old British and American slang term for a particularly strong alcoholic drink — the kind powerful enough to send you stumbling. As an adjective it means overwhelmingly powerful or overbearing, whether applied to a stiff drink, a forceful personality, or a stunning piece of news. The phrase has mostly faded from everyday use but survives in historical fiction and old pub songs as a vivid descriptor of booze that pulls no punches.