1. up-close.
2. right here, right now, in your face and/or in your ear. Used when someone is trying to prove a point.
3. the closest distance between anything that's good and bad.
A shot from some sort of projectile weapon whether it is from a gun or even a thrown object that has been made at very close proximity to the intended target which is normaly less than 20' away.
Bob being in point blank range was hit by a shot from a shotgun which completely blew off his hand.