To headbutt someone, whether accidentally or on purpose, in reference to soccer legend Zinedine Zidane's infamous headbutt on Marco Materazzi in the 2k6 World Cup Final. Most effective when you headbutt someone as some kind of sick joke, similar to Ashton Kutcher's 'punk'd' or Peter Griffin's 'tomahawk'd'.
Particularly funny if used when a Frenchman is headbutting someone, or gets headbutted.
Dude A: "That girl just tried to kiss her boyfriend on the back of the head. He didn't see her, stood up, and headbutted her. Now she has a nosebleed"
Dude B: "Ha! She got Zidan'd."