"Big Smoke" often refers to a large amount or extreme amount of smoke a person blows out, exhales, during the process of smoking.
Big smoke is a term used when
two (2) or more people gather as a group, in a room, a
car, or any place that allows smoke exhalation, (blowing big smoke), to be most visible.
When illegal drugs are used to get high, using the method of smoking the particular drugs such as meth or
marijuana. Usually done from a oil burner aka meth pipe, rolling paper,
bong, aluminum can, etc. Followed by observing of the amount of smoke in the room.