an act in which a man wraps his thumb and index finger around the outside of his scrotum so the tips of his finger and thumb touch.(above the testes but under the base of the penis)After correct placement of the finger and thumb, the hand is moved away from the body in a pulling motion. this creates a "sinching" effect and creates a hairy brain-like object from the testes bunching at the bottom of the scrotum.
because brandon liked to show all of the girls his hairy troll brain, he is now serving 1-15 years in the pokey for sexual harrassment.
by ben w. June 14, 2006