It’s a subcategory of atheism called “antitheism.” They are still 'atheists." Atheists come in several flavors. Anti-theists (Also called ‘Strong Atheists’ and Gnostic atheists, who profess to know a god does not exist.), Agnostic-atheists (who do not believe in gods), Implicit Atheists (People are born atheists and have not been introduced to gods. Everyone is born atheist and in sin according to the Church.) In all these cases, the word ‘Atheist’ fits, however, in a discussion, you should know which sort of atheist you are dealing with.
In my case, I am an agnostic atheist; however, if you try to assert the existence of a god that is self-contradictory or unable to exist, I am an antitheist concerning that god. My position can change depending on the definition of a specific god.
Theism and atheism are not necessarily opposites, as I explained previously. The jellybean jar is a good example of this. I have a jar and it has jellybeans in it. You tell me that the number of jellybeans is even. I tell you that I do not believe you. I have not said the number is odd. I just don’t see how you know the number is even. I am not asserting something opposite. I am looking at the evidence and saying, “I have no good reason to believe you.” This is the position of the Agnostic Atheist. This, I believe, encompasses the majority of atheists. So there is no opposite here.
The equivalent to Atheist ++ is the antitheist. We have dealt with many on this site. They blow in here and make inane assertions about God not existing. The people on this site are primarily skeptics, and overall, very intelligent IMO. The first question tends to be, “How do you know that?” These sorts of Christian-bashing atheists just don’t last long. That’s not to say we don’t do our own brand of bashing. However, it seems that when skeptics bash, they are careful to have some evidence backing up their claims.
I think this explained much of your concerns. If you have more questions, feel free to post. Here is a diagram that may help.
