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.
1) Meghan thinking (he's doing such a good job down there I think I'll give him a stink wink)
2) (Foul Stench noticed as John leaves the room, Dude what the hell was that?!?) It's a stink wink, you heard me right!
Produce 101 Season 2 contestant Park Jihoon became famous for winking during the ending pose of their stage "Nayana/It's Me (Pick Me)". After the video aired, he was known as "wink boy" and gain a lot of fame.
The 'Hot Wink' is when you have an upset bowel (often owing to beer and a good Vindaloo the night before) and your anus is constantly "winking" all day to hold in the impending doom.