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2.
When a rash develops around the anus as a result of profuse sweating caused by playing a gig. This condition generally effects drummers due to the friction and sweat buildup around the anus in conjunction with performance. Diagnosis can be determined by evaluating symptoms such as, redness, swelling, itchiness, and severe stench that tends to remain long after showering.
"Did you hear? After the gig Friday night Steve got a really bad case of gig butt. He was caught with his pants down scratching his ass in the dressing room. His roomates say the smell is so bad that they are going to ask him to move out if he keeps playing the drums. I am so glad that you never slept with him. Gross. If he keeps it up pretty soon he will get a nasty case of Swamp Ass."
by LoverGurl June 11, 2007
 
1.
A painful rash that occurs around your ass when working/walking in a hot climate for extended periods of time. This is caused by the bacteria around your anus thriving in a hot and dark environment. When experiencing gig butt, walking like a bow-legged cowboy is only a bandaid fix. Washing your anus (which is painful with gig-butt) is the only remedy or in a pinch, the use of baby wipes or Tucks medicated pads works wonders.
The experienced Roadie taught the stagehands how to get rid of gig butt.
by Adrian K May 06, 2005