He is what you call an agnostic. But the majority of self-professed atheists, as well as the majority of philosophers, would call that 'weak atheism.
Except, it's not. There is no organised group. Where, exactly, is it?
"Atheism is, in a broad sense, the rejection of belief in the existence of deities. In a narrower sense, atheism is specifically the position that there are no deities. Most inclusively, atheism is simply the absence of belief that any deities exist." - The 'narrow' sense corresponds to 'strong' atheism, and the general sense encompasses both 'strong' and 'weak' atheism - exactly as we've all been telling you.
"Atheism is the condition of being without theistic beliefs and alternatively the disbelief in the existence of deities." - exactly the same as what we've been saying, and contrary to what you've been saying. It's simply lacking theistic belief.
"a person who denies or disbelieves the existence of a supreme being or beings." - A person who denies or disbelieves. The two stances that are encompassed by the term 'atheism', exactly as we've been saying.
"Atheist, agnostic, infidel, skeptic refer to persons not inclined toward religious belief or a particular form of religious belief. An atheist is one who denies the existence of a deity or of divine beings. An agnostic is one who believes it impossible to know anything about God or about the creation of the universe and refrains from commitment to any religious doctrine." - Again, exactly as we've been saying.
"Many, perhaps most, Atheists simply have no belief about deity. For them, Atheism is not disbelief in a deity or deities; it is simply a lack of belief in any of them." - Exactly as we've been saying.
Atheists generally share a scepticism of the supernatural, seeing no good reason to attribute grandiose purpose or existential whining on the universe at large. And as for the origins of life, there's nothing miraculous about it (peruse Google Scholar if you're interested).
And neither do they make that statement. The vast majority of atheists, as well as major dictionaries, encyclopaedias, and philosophers, as well as government census takers, define 'atheism' as a lack of belief in deities. No more, no less.
If your personal definition of 'atheism' is 'Someone who says "There is no God"', then I am not an atheist. By that definition, virtually all self-professed atheists aren't, in fact, atheists.
The fallacy you're committing is called the equivocation fallacy. You look at organisations that proclaim to champion atheism and which are populated by atheists - but you ignore their own statements as to what they mean by 'atheism', and instead shove your own definition in its place. That is a fallacy.
