A bitch slap in which the one delivering starts with his or her hand below the waist.
Rubbernecker #1: "Oh, shit! That poor bastard just got bitch slapped!"
Rubbernecker #2: "No, no, my friend. That was an ATOMIC bitch-slap. Notice how that poor bastard's assailant pulled his hand all the way below his waist before letting loose? Man, he's gonna need to put some ice on that."