hit dog

Someone who has indicated their guilt by reacting defensively to something, usually an accusation. The term comes from the longer phrase "a hit dog will holler." A: "I just asked Paul if he knew anything about the errors in the database, and he got really angry and defensive." B: "Sounds like a hit dog to me." A: "No, I already told you, I do not like Tom in that way! We have nothing in common! There's no way we would be romantically suited to one another!" B: "A hit dog will holler, now won't it?" A: "Shut up, I do not like Dungeons and Dragons! I'm no nerd!" B: "Haha, chill out, dude. It's not that big a deal." C: "Seriously, man. Stop being a hit dog."