You (and many others) want to use the term "atheism" to mean one thing (weak atheism) and others, e.g. Stanford University, want to use another way (strong atheism). Why not just specify which one you mean?
That is absolute rubbish. The following definition of atheism:
'A person who does not believe in the existence of god or gods'
Is equally applicable to what you describe as 'weak' atheism and 'strong' atheism. And indeed those weak vs strong additions define sub-groups of atheism, if you accept the terms. That is perfectly acceptable to have variants for subgroups, but the basic definition must be broad and robust enough to apply to all atheists, and the only defining feature is that we don't believe in god or gods, hence the definition must reflect this.
Just to show how non-sense your suggestion is, just try to apply it to christianity. There is a basic definition and then ways of defining sub groups - e.g. evangelical christian, fundamental christian, census christian, cultural christian, etc etc. The basic definition must be applicable to all subgroups. If you define christian in a manner which is only applicable to an evangelical christian then I think there will be plenty of non-evalngelical christians pretty miffed with you.
I don't define it in a manner which is only applicable to an evangelical Christian, but there are actual boundaries within which a person needs to lie to be a Christian. Thus, it does not make sense to speak of a Muslim Christian (cue intervention by jakswan?).
You say that the basic definition (of "atheism") must be applicable to all subgroups. Yes, of course, but if there is a correct definition and it is
Chambers:
the belief that there is no god.
Mirriam Webster
b : the doctrine that there is no deitythen those who have
just a lack of belief in a deity (rather than a belief that there is no deity) would not be atheists by that definition. They would, perhaps, be better defined as agnostics.
However, there are considerable numbers of people who use "atheism" to mean just that a person does not have a belief in a deity (as evidenced by the OED and the other definitions quoted), so let's say that this is a valid definition as well. That leaves us with two significantly different definitions and all we need to do is say which one we are using when we use the term, i.e. say weather we mean weak/agnostic/negative atheism or strong/gnostic/positive atheism.
That is the end of my contribution on this thread. Have a good day.