A title given to a fellow hunter who is quick to jump to conclusions and continuously identifies shrubbery as game, promting the more experienced hunter to refer to the bush as green (making reference to its actual fauna appearance) and dick (making reference to the persons character for making the said mistake.
Jimmy - "Hey Salty look over there pigs!"
Salty - "Green Dick"
The act of fucking someone in the ass, and upon pulling your penis out, discovering that there is a collard green wrapped around your dick.
I met this chick that was obsessed with anal. It was the only way she could get off. In fact, it went pretty well until I pulled out one time and had a collard green dick.