
Nudge nudge, wink wink
Playful Teasing
This phrase is often used playfully, to imply a secret understanding between people without stating it outright. 
Not Literal
'Nudge nudge, wink wink' is not taken literally. It's a metaphorical gesture suggesting you're hinting at something. 
Shared Secrecy
Use this phrase when you and the listener share knowledge of the innuendo or hidden meaning. 