From episode 1 of the television series The Walking Dead:
Context: Police chase a car with three criminals inside. A bunch of them some distance away place a spike strip across the road. The car runs over it, starts swerving, turns over a couple of times. The three dudes come out of the car and start shooting at the police officers. One of them takes a bullet but the vest he's wearing saves him.
— Rick!
— I'm all right!
— I saw you get tagged, man. That scared the hell out of me.
— Me too.
What does that expression really mean? Is this slang? Something to describe a situation when someone gets shot?