Refers to a scene in the 1997 short story and 2005 film Brokeback Mountain where the character of Alma confronts her husband, Ennis about his ongoing relationship with the character Jack Twist.
Alright kids, a jack nasty is where a boy usually high school or younger who can't get laid masturbates 'jacks off' into some tissues. Since he is often not one to properly discpose of them, they drift about the room and eventually make their residence beneath his bed.
The resulting hard, crusty tissue wad peeking out from beneath the mattress... Is a jack nasty.
Unfortunate genetic disorder or botched female circumcision in which the vagina and uteral region appear as though Crocodile Dundee went dynamite fishing in the female genitalia.
While she was doing the human pretzel, I gave the Chinese gymnist a jack nasty face with a sledge hammer, some barbed wire, and egg beaters.
Mas: Those nasty jacks are really startin to get on my nerves
Retep: the fat 1 with the fro is the worst
Mas: no doubt, one that i can stand is steven
Retep: hes cool