The act of betraying someone. It's comparable with anime betrayal
He fucked his friend's girlfriend, what a cock over
Cross-overization,
a noun form of "cross over", which can already be used as a noun
Zhang just made a cross overization on Yang.
based on the ads for Diamond Shreddies, it means to argue over things that are basically the same.
"Dude, that's a circle,"
"Naw man, it's an oval!"
" Oh, come on stop fighting over shreddies!"
"Is that a husky-terrier, or a husky-poodle?"
"Dude, it's a dog, don't fight over shreddies."