look up any word, like cunt:
 
1.
Its when a girl is on her knees sucking a guy off who is standing up and right when he's about to explode, he pulls out, shoots it in his hands and rubs it together. Then he slicks both sides of the girls hair back and says, "HEY"!
Did you see that girls hair, she must have gotten the fonze last night.
by Kris Wick February 21, 2007
 
2.
When you are doing a chick from behind, you shove your thumb in her ass and yell, "Heeeeeeeeeeeeeeeeeyyyyyyyyyyyyyyyyyyyyyyy"
While doing my chick i asked her if she likes Happy Days, when she questions it, you give her the Fonze
by ElMartiniMan December 13, 2009
 
3.
The act of shoving both your thumbs into a females anus and saying, "AAAAAA!"
Bill: Remeber that dishrag whore form the bar last night?
Tom: Yeah.
Bill: I gave her the Fonze.
by mrducks December 19, 2003