When you're walking or hiking and have to pee but can't afford to stop, so you turn around and start walking backwards so that you can pee while you walk without getting pee on yourself. The maneuver is named after your exposed cock and balls resembling a turkey beak and waddle. Also called a "walking turkey" or "hanging donkey."
I had to pee during that marathon but didn't want to lose any time, so I turned around and pulled a lil' hanging turkey.
U strapped. Pretty simple but slick as hell.
They know don’t play cause my thigh hang low.
Limp penis due to cannabis consumption
Can’t tonight honey I’ve got the Mary Jane Hang.
To stand around with nothing to do whatsoever.
The doors don’t open until 10, so we’ll just hang balls until then.
taking your girlfriend while she is sleeping and hanging her upside down and face fucking her.
"Dude you have to try the hanging bat on your girl."
Apart from the original Richard Keys usage of the phrase, to hang out the back of something can be used as an expression of approval of something well done.
(after eating a good meal cooked by a friend) "that pasta was great, you really hang out the back of it"