Facial Hair: When a young man, not yet able to grow a tasty moustache, grows about 8-9 hairs on his upper lip. It only slightly resembles a moustache, but more-so resembles poop.
(Can also be called a dirtstache, shitstain, or mancrap)

When you eat dirt for the first time and leave your family to build a shack in the woods

1. The unsightly, visible hair on a man/woman's upper lip that isn't quite mustache material, but is reminiscent of a pubescents upper lip hair.

2. A deposit of excrement on the upper lip of one who has recently commenced the act of taint/vaginal tongueing on a subject residing in the doggy style position .

3. The jovial result of a dirty sanchez.

A fecal mustache, acquired from excessive ass kissing.

1. The unsightly, visible hair on a man/woman's upper lip that isn't quite mustache material, but is reminiscent of a pubescent’s upper lip hair.

2. A deposit of excrement on the upper lip of one who has recently commenced the act of taint/vaginal tongueing on a subject residing in the doggy style position .

3. The jovial result of a dirty sanchez.

A prank usually played on a sleeping individual. The giver of a poostache takes a finger to his own buttcrack until said finger is ripe with stink. Giver then rubs finger across upper lip of receipient. Also know as a stinky sanchez.

a moustache that looks like it was rubbed in with poop.