skid mark
A fecal stain that is visible on one's undergarments.
Also presents in a less structural (and lesser known) form, typically developed from excessive "dry farting". In this form, the skidmark develops in a larger region, yet its definition is not as clear. Essentially, it is representative of a consistent gaseous pounding of one's underpants over a long period of time, and while fairly rare, is unmistakable. Usually, this effect is understandable to about 1/10th of all humans.
Also presents in a less structural (and lesser known) form, typically developed from excessive "dry farting". In this form, the skidmark develops in a larger region, yet its definition is not as clear. Essentially, it is representative of a consistent gaseous pounding of one's underpants over a long period of time, and while fairly rare, is unmistakable. Usually, this effect is understandable to about 1/10th of all humans.