The act of inserting a thumb into the anus during intercourse. Inspired by the Happy Day's character,Arthur Fonzerelli, who was fond of giving the thumbs up and uttering "Aaaaaaa(nus)."
"We were doing it doggy style when Christian decided to give me a dirty fonzie! I felt so violated!!"
Greeting: A sign of ones own coolness by sticking both thumbs up while wrist reman parallel to each other with elbos placed at the waist. Jiggle hands for enhanced emphasis upon coolness.
I threw fonzies in the wrong office and everyone thought I was there to fix the broken record player.
Even though you're throwing fonzies you still cant jump a shark in a leather jacket.