wink / blink

wink

to close one eye and open it again quickly, 
especially as a private signal to someone, 
or to show something is a joke

He winked at her and she knew he was thinking the same thing that she was.



blink

when you blink, or blink your eyes, or your eyes blink, 
you shut and open your eyes quickly

He blinked in the bright sunlight.




http://oaadonline.oxfordlearnersdictionaries.com/dictionary/wink
http://oaadonline.oxfordlearnersdictionaries.com/dictionary/blink