rusty bathtub Share definition Flag An asshole with a dried ring of poop all around it giving it the look of a rusted bathtub. Guy 1: Did you try anal with her last night? Guy 2: Nah man, she had a major rusty bathtub! rusty bathtub by SkrappyParks July 9, 2011 0 0 Get merch Get the rusty bathtub mug. Buy Now — $32.95 See more merch