Can someone explain Atheism to me?

The definition of atheism is defined as being the opposite of being a theist. Literally without god. The very definition gives credence to their being a god. Also cited is the argument of lack of empirical evidence, however by asking for empirical evidence to be supplied to support the existence of god, aren’t they subject to the same criteria of having to empirically prove god doesn’t exist? What I am getting from this and I can admit it’s an oversimplification is that they choose to believe that god doesn’t exist, which makes them as much a faith oriented creature as a theist.

This isn’t meant as an attack on atheism. I am spiritual but not religious or constrained by any deity. I feel there is not enough evidence in either direction. I am genuinely curious as to the apparent flaw in logic. So if I am mistaken on my premise I would like to know why.