Air ( poker )

1) In a lowball game, letting another player know whether you are going to draw cards or not,
sometimes letting the player know how many, usually with the intention of getting that player into the pot.
Usually part of the phrase give air. "Gimme some air. I'll draw two if you're drawing one."

2) Inadvertently exposing cards; usually part of the phrase put air into [a hand].
"You'll like sitting next to Johnny; he puts a lot of air into his hand."
That is, if you sit next to Johnny, the way he holds his cards you can often see some of them,
which, presumably, gives you an edge (albeit an unethical one) on him.