Dropping your pants (trousers) for no apparent reason at all.
It's night time and a guy is standing on the side of a deserted road. Out of nowhere a car starts heading towards him. From the driver's perspective you see the lights getting larger on the person. The person then look directly at the driver, eyes wide, then just drops his pants to the ground and darts across the road so as to pass in front of the car narrowly missing being hit. It can be said that the man has just dropped trou' and bailed.
by Jason K. August 22, 2005