1.)Refers to one being nasty in the sense that they are dirty and undesirable for sexual purposes, and/or any other purpose that requires someone to be clean, groomed and presentable in public or private.
2.) To be so nasty as to resemble the smell, color, or shape of an anus.
- more commonly known as: Ass-nasty
Billy Bob: "Are you serious man? That chick is ASSHOLE NASTY. I would have sex with her her if she was the last woman on earth".