Actually the term agnostic is very well known, but to be clear, you are neither of these, as you are not an atheist. Atheism is not believing in any god, instead of rejecting known religions but still believing in God, such as yourself. Atheism is a belief system like any other. Agnosticism, like the definition above, is often used when people feel they don't know enough to tell, or they don't care.

TL;DR - You aren't atheist, as that would mean you don't believe in any gods. Lacking a better term, you're simply a theist. Here's a useful image about these things: