swamp ass
n.— «Just quit wearing underwear…thats what i’ve done…it’s way too much bother. Although come summertime it’s real easy to get a case of “swamp ass”…ohhhh…the itching…it’s dreadful.» —“Re: how much do boxers cost?” Usenet: alt.punk Nov. 9, 1997. (source: Double-Tongued Dictionary)