Used to declare dominance in regards to riding in the seat directly behind the front right seat in a vehicle. This is because that seat is behind the "shotgun" position.
4 friends walk up to a car.
Person 1: I call shotgun
Person 2: I call Mcnair
Person 3: damn, now I have to sit behind the driver.
This is because of how mcnair was behind a shotgun..
Call "cobain" instead..