For too long atheists have been granted a free pass to deliberately dilute the definition of atheism. Too many active and passive atheists are quick to assert the informationally deficient definition of atheism widely known as "a lack of belief in God" or the "absence of belief in God." They would like nothing more than to believe they have no beliefs about God and merely possess an "absence" of a belief. After all, that is the regrettable definition found in some dictionaries (UrbanDictionary.com, Definition 1), and is, conveniently for the atheist, much easier to defend than saying what you actually believe about God. Consequently, today's atheists are more eager to tell you their beliefs about atheism than they are their beliefs about God.
The lack of substance in the popularly held definition of atheism among atheists makes it altogether unsatisfactory when discussing beliefs about God. The only information this definition conveys is that atheists have no positive belief in God. Atheists like to propose that a "lack of belief in" absolves them from possessing any belief whatsoever. However, an "absence of belief" doesn't negate the prospect of other beliefs or disbeliefs around the subject. In fact, it actually demands it. Stating you have an absence of belief in God says nothing about what you believe about the God.
Perhaps this is why some dictionaries also define atheism as "a: a disbelief in the existence of a deity. B: the doctrine that there is no deity." (Merriam--Webster) "A person who believes no god or gods exist." (Urban Dictionary, Definition 2). This is a meaningful definition of atheism one can sink their teeth into. This accurately informs me and the world what atheists actually do believe about God. Most important for the atheist, it is in line with reality. Atheists do have beliefs or disbeliefs regarding God, just as they have beliefs and disbeliefs regarding heaven, the soul, and the afterlife.
When approached with such celestial concepts, an atheist does not try to conceal their actual beliefs by saying they have a "lack of belief in" a soul. They properly state either a positive belief that there is no soul, a negative belief that they don't believe in a soul, or on rare occasion, a belief in a soul. The atheist is perfectly willing, and able, to state their beliefs regarding this and other supernatural propositions. Should God be an exception? Of course He shouldn't be.
Whether it be heaven, a soul, God, or a favorite atheist god, The Flying Spaghetti Monster, one takes a belief or disbelief on the concept. The introduction of the idea forces the conscious and intelligent human brain to automatically deliberate the proposition, especially ones of such magnitude. We then formulate and hold beliefs or disbeliefs in our mind. Atheists have had many years to deliberate the concept of God and have formulated numerous beliefs and disbeliefs over their lifetime. Unless an atheist's head has been buried in the sand all their life, it is impossible in our civilization for them to have not acquired some actual beliefs about God. In reality, atheists either believe there is no God, or don't believe in God, in addition to having a "lack of belief in."
If atheists applied their own definition of atheism to their divine creation the Flying Spaghetti Monster, an atheist would proudly state they merely have an "absence of belief in" the FSM. Just as with the theist's God, they would neither concede to having a disbelief or belief . I have no qualms confessing that not only do I have a "lack of belief in" the Flying Spaghetti Monster, I also positively believe the FSM God does not exist. Are atheists willing to concede a theist has more conviction that the Flying Spaghetti Monster doesn't exist than an atheist does? Perhaps now atheists can fully see how incomplete and wanting their definition of atheism is in practice.
In truth, atheists have much more than simply a "lack of belief in" the Flying Spaghetti Monster and would concede they don't actually believe in him. Since the Flying Spaghetti Monster is the atheist equivalency to the theists' God, they should similarly admit their beliefs or disbeliefs about God.
Atheists stating atheism is nothing more than a "lack of belief in God" are simply using that definition as a copout. They are hiding behind an insufficient definition of atheism so they won't have to confront what they actually believe about God. Atheists are quite willing to accept they have disbeliefs regarding other supernatural phenomenon and the Flying Spaghetti Monster. It is time they became reconciled to the fact that they they don't believe in God as well.