Also known as SMH standing for "shaking my head"
B: oh, you shake your damn head cuz studying's so stressful.
A: um, sure, lets go with that.
Example2: I got out of the shower at my girls house. She was watching american idol in the bedroom. So I stood in front of the tv, dropped my towel, smdh shakin my dickhead and broke out the helicopter on her.
Dude 2-"Sigh...smDh at you."