Gorilla Knuckle
The outline of the edge of a guy's glans ridge through his underwear or pants.
Check out that guy's gorilla knuckle- he's got it pierced!
gorilla knuckle
(verb);to gorlla knuckle-During sexual intercourse when the individual on top has both arms hyperextended with all of their weight on their knuckles or wrists. The lower body (with exception to the member) is flacid, allowing the arms to control the majority of the motion.
Billy has nasty rug burn on his hands becuase he gorilla knuckled too long last night.