look up any word, like hipster:
Used to describe a situation where you and someone else are aware of the mistake that a 3rd person is making. For this to be an "I know, you know." the 3rd person should be blissfully unaware of the situation.
"Hasn't Yoshi twigged that bird over there is a shemale?"

"I know, you know."
by Scotsdave December 02, 2004

Words related to I know, you know