How would you translate the phrase "punch line" (of a joke?) In English, it is customary to say that a joke has a "punch line." The punch line is the last sentence or phrase of the joke. Until you hear the punch line, it is not clear why the joke is funny. It just sounds like a story. The joke builds up to the punch line, which suddenly reveals the surprise, the incongruity. The punch line is the place where you laugh, the climax, the line where you "get it," where it "hits you," the line that "delivers the impact." (Setup) A husband is standing on the bathroom scale, trying desperately to hold his stomach in. His wife says "I see you're trying to hold your stomach in, but that isn't actually going to make you weigh any less." (Punch line) The husband says "I know, but my stomach is blocking my view of the numbers."