1) Also known as ass wink or A Brown Pucker. When a chick flexes her anus in the 69 position this is a "Stink Wink"
2) Farting as a response or greeting.

The act of extreme masturbation. You must "knock one out" whilst in close proximity to any of the following; Your mum, a nun, your boss, a member of parliament, George Michael. A person with capabilities to act upon catching you mid self-abuse obvisouly ups the ante. Ejaculation must be reached before your danger wank target comes (no pun intended) to investigate. The higher the chances of being discovered with one's pants down, pulling one's war face is obviously where the danger comes from. The more danger involved the harder (or softer) it is to complete the task in hand (snigger). The more dangerous the better. The chance of being arrested, pummeled by an angry father or having your hand severed by an arab's sabre means that you are a pro "Danger wanker."

The quasi-sexual procedure of a man sticking his index finger into his female partner's rectum and then proceeding to poke her in the eye with the contaminated finger.

The flex your anus makes when you fart

When you moon somebody and fart and your butthole winks when it opens to release the fart.
Fart stank butthole greetings

The act of bending over a woman, licking her asshole, and blowing a tuft of air into her balloon knot and watch that brown eye wink at you.

an animal who's tail is up showing their "stink wink"