There is no defined explanation of the meaning of a wink. It's all in the context of the moment.Winks, nods, raised eyebrows all are essentially facial emojis which accent the meaning the person is trying to convey. In American culture a wink could mean:
- I am just teasing your when I say that
- Did you hear what the person we're talking to said? He doesn't have a clue.
- Don't let anyone know i'm in on your joke - Ill play along.
- Something blew in my eye
- I think you're special/cute/ potentially interested in me
- I have a tic in my eyelid or I can't see well
If you can't guess what the wink is supposed to convey the winker is poor at his game and might need to try a bit more talk to make himself clear.