This was first used and named after a great football player in Texas. Used when having sex with a girl that has a good body and a not-so-good face. While having sex, from behind of course, if the girl turns around to look or say something, the opposite arm is used in a stiff-arm motion to turn her face back to the front so that you do not have to look at her.
"I used the Bo Johnson stiff-arm on that girl while I was fucking her, and thank God, because her face was aweful."
by Gilbert A February 13, 2006