If it's not natural, it's unnatural
“Atheism” isn’t a proper title. It’s defining something by what it isn’t. It doesn’t suggest any unique attributes. It doesn’t say, “this is what it is”, it says, “this is what it isn’t”. I may not know what atheism is, but I’m pretty sure it ain’t that chair over there.
“Supernatural” applies to anything that isn’t natural. There’s what is natural and then there’s everything else. You could say that if it’s not natural, it’s unnatural. (That’s my new catchphrase.)
