A sexual position in which a/the female lies down while her partner hangs above her by his or her feet. With proper control, her partner can swing back and forth, performing oral ministrations on her each time his/her head swings by the appropriate areas.
That was some crazy shit last night. I ended up doing the Pit and the Pendulum on some girl and almost fell and broke my neck!
A sexual position in which the female lays in the jackhammer position and the male enters her from the front with his ass hanging over her face. He will then defecate (note: it must be a log or the metaphor won't work) and let the log swing back and forth before it falls, thus "The Pit and the Pendulum."
That bitch was crazy last night, she wouldn't fuck me till I did The Pit and the Pendulum again.