One of the tell-tale signs of a chronic user of methamphetamine (aka glass, crystal, meth, ice) is the meth smirk. Muscle rigidity sets in on the muscles of the mouth and the user will sound like they have some kind of speech impediment, as if they are unable to fully close their mouth while talking, and look like a smirk is frozen to their face. Described as sounding twacked out.
A: "Wow, Bam Margera's really got a solid meth smirk goin' on in this episode. He can barely talk!"
B: "Yeah, he's fuckin' twacked out."
B: "Yeah, he's fuckin' twacked out."
by Tommy TapeShoe October 27, 2010