When a girl talks big but never actually does anything. They make a scene and act tough but in the end they don't do a thing. They say they'll hit this girl or yell at this guy but nothing ever happens. At the end of the day, they know they would never actually do anything, and so does everyone else.
Girl: Tomorrow I'm gonna go into his classroom and yell at him.
Guy: Bullshit, your just acting brirrational.