An abrasion on some area of one's skin resulting from falling off of a non-enclosed vehicle (such as a bicycle, motorcycle, skateboard, etc.) and onto the pavement. A: "I just ended up with a bit of road rash on my arm." B: "You're lucky you didn't get killed! Next time, you wear your helmet on that bike, do you hear me?" My motorcycle slipped on some gravel and I went skidding on my back about 100 feet down the road. I got such bad road rash that I had to get a skin graft!