A self-appointed, self-aggrandizing nickname chosen by a loser who wants to appear important or cool, despite the fact that they were never in the military and were never cool.
Person 1: That dick wants everyone to call him Sarge now.
Person 2: Yeah, what a loser! Nobody actually calls him that except some kids and a demented old man.
Being the middle person in a line of smokers, and taking extra drags when thecigarette, joint, or preferably blunt is passed.
See example in RvB Season 4 episode 2.