What is Air Up?
1.
Southeastern Missouri term. Not sure if it's known of elsewhere. To inflate; to fill with air.
Near the back of the car... BAM!!
Passenger: What was that??
Driver: -sigh- I think we've got a flat tire. I'm gonna have to air it up.
Driver pulls over to the side of the road, gets out his inflator thingy to air up the tire, and bla bla bla you get the point.