We have a definition of the word, just like for any word.
I think that is the wrong way to frame it, as it just sets up a tautology, empty of content, through the synonym "good" for "moral" and "evil" for "immoral." It says nothing. It frames the issue as this horribly abstract, metaphysical conundrum, whereas, in the real world, if you don't care where you're walking and you bump into me, that's immoral (perhaps that the lowest level).
In the real, concrete world, what is the actual content of morality? The best answer I've heard, that makes sense, is the well-being of conscious creatures.
Thinking that any goal can be moral (and I meant something different when I said "Anything is possible," see below) is like thinking you can eat anything you want, including glass, cars, etc. (even while some people have). It's nonsensical philosophizing. I recommend we get real, instead.
I didn't mean that in the way that you took it. I wasn't trying to include anything into morality, I was only saying that people can conclude anything about morality (sensical or not).
But they're not equally valid if we take morality to be something actual, and has great significance in the real world, and not some abstract philosophical essence. It's not like it makes sense to decide that anything can be food, and all food is equally valid/nutritious.