Basically, it can mean "very," "very good," or "very X," where X is an attribute frequently associated with the hellafied object in question.
Not to be confused with [hellafried], hellafied comes from the back-formation of [hella], queer-ass California slang for "very."
This site has definitions for [hellified], an alternative spelling of the term.
> "The bitch sucks a hellified dick."
> - Dr. Dre