A state of being after general uncleanliness leading to so much sweat that one's lower region could possibly produce the vegetation and smell of a swamp.
Man that dude Edward Malone has swamp-ass, I heard he doesn't shower in weeks.
Common among military tuck drivers deployed to Iraq. Occurs when the seat of the vehicle absorbs the swamp ass from one driver then before it can dry another driver mixes their own sweaty swamp ass in the seat cushion resulting in a swamp ass soup.
Dude, you swamp assed this seat. So. Well I got swamp ass too and now we just created swamp ass soup.
A condition in which your buttocks and other nearby regions get overly moist often causing discomfort resembling the feeling of not wiping your ass. This happens typically when working in intense heat, during masturbation, refusing to wipe, and some other isolated situations. Also, this condition leads to a not so pleasant stench often leaving you extremely self-conscious if the situation cannot be remedied immediately.
Bryce-"Why were you walkin' all funny today when you came into work?"
Slade-"I'd been outside waiting on the bus and got swamp ass."
Bryce-"Word?"
Slade-"Word. I had to go to the bathroom and handle it quick before that fine ass new girl saw me or else she'd think I'm dirty."