Extreme fetid from one's mouth. Mostly due to the lack of drinking water, eating fruit and vegetable, and poor digestive system.

The smell is characterized by its foulness, significantly different from ordinary smelliness from forgetting to brush one's teeth in the morning or eating some pungent food (durian).

Shammouth is a result of prolonged unhealthy diet and constipation which renders the smell of one's shit being raised to the level one's mouth.
dude 1: what the fuck is this fuckin smell
dude 2: not me
dude 1: of course it aint u, its ur shammouth

dude 1: what the fuck is this fucking smell
dude 2: not me, i hvent opened my mouth since u were here
dude 1: (spotting dude 3 talking 5m away) fucking shammouth that guy has.
by Gloria Sam1 June 15, 2010
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