Guan,
pronounced 'gwaaaaaan', is a coloquial term used in place of
the words marijuana or cannabis. In the UK, it is a class 'C' drug, though is of late often mistaken as being legal by many youths. The drug is usually taken via smoking, which usually involves rolling a cigarette with rolling papers and rolling tobacco, adding ground guan to the cigarette, and smoking the end result.
"Word up Thomas, what ya ridin' out to?"
"You know, chillin', waxin' lyrical to
the track and smoking a fat sack of guan."
"Mmmm, nice. Ya wown a leaf up a greezy bodeyga?"
"Say word son,
you know how we do. Time to
crack-a-lack down the back track of a flap jack!"
"Damn you clownin' foo', you need to get up off of that gasoline."