(Sorry if this topic has been beat to death in a million other posts & blogs on AN, but here it is again anyway...)

I'm a bit hung up on definitions of atheism at the moment.  Such a basic word shouldn't be this fuzzy.

After pissing a bunch of people off by telling them that atheism technically means "lack of belief in existence of thesitic gods", but does not necessarily mean "belief that theistic gods definitely don't exist", I find that it's pretty hard to back that up w/ dictionaries.  Dictionaries all claim it means a positive claim that there is no god.  Further, they don't distinguish between theism and deism.

In the examples below, we do get "godlessness" as a secondary meaning, and we get "without a god" as a root, but that's it.  Only the Oxford dictionary comes close to what I expect with "Disbelief in a God" which does mean "lack of a positive belief", but still does not differentiate theism, unless that's why there's a capital "G" on god.

Shouldn't the definition say "lack of belief in any god that fucks with people's lives"?  Should I continue to fight that the dictionaries are wrong?  Or do I just give up and go with the dictionaries?

Webster's New World Dictionary, 3rd College Ed.

atheism
1. the belief that there is no God, or denial that god or gods exist
2. godlessness

atheist
a person who believes there is no god

The American Heritage dictionary, 3rd Ed.

atheism
Disbelief in or denial of the existence of God
< Gk. atheos, without a god.

A Student's Dictionary & Gazetteer, 18th Ed.
(freebie school dictionary from The Dictionary Project and donated by The Elks)

atheism
the belief that there is no God

www.oed.com (Oxford English Dictionary online)
atheism
Disbelief in, or denial of, the existence of a God. Also, Disregard of duty to God, godlessness (practical atheism).