Any person that when they bend over has hair coming out of their butt. Referred to as a "rainbow ass" because it is popping out as rainbows do from clouds.
by kgriff January 6, 2012
Get the Rainbow Assmug. by Momo Hatake May 7, 2007
Get the rainbow ass munchermug. An imaginary meteorological event occurring after a severe bout of diarrhea, much as a rainbow occurs after a thunderstorm.
by Barbiste May 26, 2004
Get the ass rainbowmug.