another way of saying just chilling. or nothin....common replies to the question of "whats up?" or "whats going on?"
the means in wanting to "get some" or have some sort of sexual activity with the opposite sex
guy1: hey yo dood? was good?
guy2: aw jus hanging brain man.
guy1: what do you wanna do mayne?
guy2: all i know, is i wanna hang brain!
guy1: k lets call some girls!
The act of pulling one's scrotum (testicles included) through the opening in one's pants or shorts, thus exposing the beauty of one's gonads for all to admire. Named for the remarkable resemblance of the display to a human brain, hanging in the breeze.
Dude was hanging brain at The Coney for almost an hour before he got busted by some chick drinking Yeungling.
When your balls hang out the leg of your shorts and you are not even aware of it.
This commonly occurs when you lean back and put your legs up, while in a seated position and you're rockin short, loose-fitting bottoms, i.e., short shorts or short swim trunks.
Being stoned helps, too.
This occurs with a much higher degree of frequency in wearers of boxers than in wearers of more supportive undergarments.
Did you see that? Tom was hanging brain the whole time he was hitting on that chick! I wonder if she noticed?