When someone has acne right above there upper lip that resembles a mustache.
dude-man u got an acne-stache
dude-get some proactiv and trim it
When someone has a ton of acne above their upper lip, making it seem like they have a mustache made of acne. Is noticeable, but the acne usually isn't too bad.
Person 1: "Ew! That guy has such an acnestache.. he should grow a real one to cover it."
Person 2: "It's not that bad..."
It's a collection of zits above the mouth and below the nose that resembles Hitler's moustache due to the location.
Person 1: Did you see that Zitler Stache that Jeremiah was rockin the other day?
Person 2: Yeah he looked dirty, offensive, and racist all at the same time!