Does any credible dictionary or philosopher accept the definition of atheism as "a lack of belief in God or gods"?
No. Atheism is CHOSEN disbelief in any deity or religion. It is not a LACK of anything!.
"Atheism is discovered not chosen" Christopher Hitchens. I did not choose to become an atheist. I came to the realization that God does not exist. I could not believe that Scooby Doo is a real Dog if I wanted to. Neither can I believe there is a God. I do in fact lack a belief in a God.
I certainly did not CHOOSE to be an atheist. I just gradually , quite early on, realised that there is no theistic deity up there in the sky or anywhere else. It's not a religious belief brought about by a sudden conversion or whatever It's just a gradual understanding.
@AMGT I respectfully disagree. Every decision we make, including the decision not to believe in any deity, is a personal choice. We analyze facts and information and choose to believe as we do. If we act in facts and reason, the choice is a rational one. If we act on emotion, the choice is irrational.
You can respectfully disagree all you want, but it's not a choice, it's a conclusion, based on investigation of facts and evidence.
@RationalHuman A conclusion is a choice. Further, even if a conclusion were simply a determination, that is only a mental concept. Becoming an atheist is an action. All of our actions are based on choices. I think you are trying to play semantic games to avoid admitting that atheism is a real choice.
Either you are being willfully obtuse, trolling, or don't understand the English language. Please describe the action you take to become a nonbeleiver in the flat earth. Did you make a choice to not believe? Can you just as easily make the opposite choice, to believe in a flat earth? You probably believe sexual orientation is a choice too.