The imprint that is left on the back of a toilet seat by someone (usually a fat ass) who has not been diligent in wiping. The combination of sweaty ass-crack and residual shit results in the depositing of a brown streak on the toilet seat. Most commonly found in public restrooms.
Man, I really had to take a dump this morning, but someone had left a crack-track in the first stall. So I moved on down the line.
by fishinmusician December 11, 2009