1.) A milder form of swamp ass, sometimes caused by a trickle of backsweat down the crack, usually on a female, can be very sexy and make you want to do butt.
2.) Early-morning swamp ass
3.) A classier term for swamp ass

Incidentally it is easier to encode "dew butt" into common speech to signify that your ass is sweaty to knowledgeable listeners.
Gent 1: Dear me, but I'm afraid there is a wetness in the crack of my bum!

Gent 2: Ah yes, with the heat and humidity being as it is, I fear I too have the dew butt.

When girls get dew butt that means no lube necessary.
by testicles...that is all June 22, 2010
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The ring of sweat left on the toilet seat upon getting up after a particularly problematic deuce.
The butt dew glistened after I put one through the hoop.
by Storpy July 21, 2011
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