dirtstache
A thin layer of facial hair on the upper lip that looks like dirt was smeared over the persons face.
Look at AJs dirtstache, did he dive into a pile of shit?
dirtstache
n. A layer of dirt on the upper lip and nose from riding dirt bikes/ATVs in a dusty region, particularly where the helmet does not cover the face.
I was riding behind you for miles, all that dust gave me the worst dirtstache!