A Meth Fart is a build up of noxious, putrid, and sometimes toxic gasses that accumulate inside of a meth atticts tweeker colon. Meth farts usually occur after a 5-7 day meth binge. They are usually induced by a large piece of pizza or a blueberry danish. Sometimes they smell like burning rubber on the side of the freeway. You can usually tell how much a person does by duration of the flatulence. Some can last up to 90 seconds. Tighter sphincters create louder, more trumpet like exclamations of gas.
Bill: Hey Jan!
Jan: Hey Bill!
Bill: Do you smell that offensive odor? It smells like a dead carcaus.
Jan: Yeah I smell that, Lori just had a massive meth fart before leaving my trailer.
Bill: Oh wow, that's ripe. How long did it last??
Jan: Ahhh gosh, I dont know, like 40 seconds. It woke up my cat.