look up any word, like half chub:
 
1.
a stain found in your undies.... like after you have a viscocity fart
i have a fart stain!
by Ciske November 02, 2003
 
2.
visible markings left typically in the undergarments of a personage having passed a flatus can be a spry alluding to a person as useful as the preceding definition
As Johnny disrobed his boxers sported a mustard brown fartstain.
by schultheis, sj July 04, 2006
 
3.
Name for someone who has skidded in their pants,
this can be adapted to many names, including the words, stain, skid, mark, fart, brown.
"Hey did you know that Ben skidded in his pants?"
"Hahaha GO ON FartStain"
by Dan.Smith November 20, 2007