To have sex on or around the Thanksgiving holiday. "Turkey neck that cavity" referring to the penis-like appearance of the turkey neck, being stuffed into the turkeys body cavity—resembling a wide-open vagina. (See also: "Stuff her with your giblets")
"Spread out Autumnal-themed tablecloth and get your ass on the dining table; I'm gonna stuff you w/ my giblets and t. neck that cavity!"
E.T. (The Extra Terrestrial) had a long neck and a large head. When someone stretches their neck and their head blocks your view.
"I can't see because you are E.T. Necking!"
As your friend looks out the window and says "Check out that girl over there!" and you cant see past his head because he is E.T. Necking and you miss the view.
Ruler of Lake Titicaca. Rumored to have a bunghole that gets very angry if it does not receive toilet paper. Cornholio the Great is often seen walking around with his shirt over his head and his hands in the air, chanting songs about his power, and his bunghole.
"I am Cornholio! You do not want to face the wrath of my bunghole, for I need TP!"
Butthead: Shut up, Beavis! (uh huh huh huh)
Beavis: Um, okay. (heh heh heh heh).