Noun

1. A long black mark left on a road surface from the sliding or skidding tires of a motor vehicle that has lost traction.
2. Any other mark or stain caused by one surface skidding along another.

   The ladder that slipped left a skid mark across the tile floor.

   The girl had skid marks on the knees of her jeans.

3. A visible feces stain left on underpants, trousers, or sometimes the toilet bowl.
4. Any burn on the skin caused by scraping the skin against a surface.