floating a brain 

One "floats a brain" by pulling your testicles out of the fly hole of your pants and proceed about your normal business without acknowledging the exposed genitals. This is typically done in bars or at parties.

I floated a brain at the party last weekend. I will be floating a brain this evening at the social function.

floating a brain by bigEC July 19, 2014

Floating Brain 

The bare ball-sack of a young and highly promiscuous young man!

'"I'm going to give you a floating brain in the face!"
":O"

Floating Brain by John from 17 March 3, 2010