Typically used to describe an annoying brother who is inclined to hurt himself frequently using sharpened sticks, rocks, vehicles, stairs, or whatever is most readily available.
I called my brother Ethan a butthead face dog cur yesterday after he sat on my bed while I was trying to talk to my boyfriend on the phone.
Mad Dogging Face, or "MDF," is when a male constantly has a pissed off look or scorn expression on his face.
Male equivalent to the female version of Resting Bitch Face, or "RBF."
"That new dude, Sam, at the gym seems cool, but he has MDF. He needs to smile more to break that Mad Dogging Face."