Maybe look up atheism then try correcting your own comment instead of theirs :)

In all seriousness, I think your definitions are a few centuries out of date. It’s been drifting toward meaning a-gnostic instead of undecided. Contemporarily, it’s used to explain one’s believed level of knowledge on a claim. I can, for instance, be agnostic toward plate tectonics, and be made gnostic of them by evidence.