The act of transferring your under arm odor to another person's upper lip, typically via one's index and middle fingers. This results in a recipient who constantly smells your BO. Best accomplished when target is unaware of their fate until it's already too late.
Style points awarded for shouting "dirty armando" while act is in-progress.
After working out together, I thought it'd be funny to give my girlfriend a dirty armando. She didn't laugh.