similar to a backseat driver (where someone tries to tell the driver how to drive from the backseat) but instead of the backseat, they criticize your driving from the passenger side seat. a.k.a. shotgun
passenger: turn to the left a little, you're on the white line.
driver: dude, stop being a shotgun driver.
driver: dude, stop being a shotgun driver.
by k-dizzlefosho January 30, 2010