Cloud Ball Gas - An large cloud of putrid gas pushed out of the anal region tending to linger in a room or on a public form of transportation like a bus.
The smell tends to burn the nostrils and will make breathing difficult as well as potentially induce vohmiting. In some cases death can occur from asphyxiation due to an instinctual reaction to hold one's breath while being exposed to the cloud.
I can't breathe someone must have dropped a CBG on the bus.
It smells kind of like a car backfired or a buffalo's asshole it must be a CBG!