"That was a crazy wipeout."
-"yeah, it was hainus, he tore himself a new asshole."
or
"my girlfriend dragged me out to see britany spears, the whole concert was hainus... but at least there were some hot chicks."
Chiefly Southern U.S. var of haunt, originally, but the meaning has since morephed to mean more than a ghost. It can also mean a scary bitch or mean person, usually a woman.
I tried to kill her with kindness, but that haint is just full up with meanness.