pretty much the same idea as bellybutton lint, but it is lint from the underwear that resides in the general area of the butt crack. usually gets caught up in the hair in the butt crack.
hey shut your big, fat, dumb mouth or ill stick my butt lint in your nose!
Buttmint--like a breathmint, but for your boyfriend's or husband's butt. Used when double dating occurs and friendly competition (wii bowling, archery, etc) and beer drinking games and wagers are combined together to create an unholy stinkiness that burns your nostrils and singes your nose hairs and makes the girlfriends or wives wonder if they are going to have to wash brown streaks out of their "better" half's undies. Buttmints are needed when you must create a "fart-room" that "better" halfs must go to, to release said unholy stinkiness. Buttmints are needed when a boyfriend/husband thinks they have shat themselves (yes, shat--past tense of shit) when they have only just farted. Hopefully they will be coming to a store near you. Patent pending. : )
"Oh my God. I'm going to throw up because you stink. We have guests. Go to the bathroom. You need a buttmint."