So PZ Myers is unhappy with the “dictionary meaning” of “atheist”:
You can’t possibly pretend that Ayn Rand and I are similar kinds of atheists…but if you just strip it down to its literal meaning, that’s what you’re left with…an utterly useless, empty word that throws all those diverse thinkers into the same arbitrary bin.
It’s an oddly presented complaint. Firstly, no one is pretending that PZ and Rand are the same kind of atheist, and that isn’t “what you’re left with” by identifying them both as members of a larger category. “Atheist” is what linguists call a lexeme, a general conceptual category (like “blue”) that can then be subdivided into smaller units (like “periwinkle” and “cyan”). PZ is upset that his periwinkle might be tainted by association with Rand’s cyan—but like it or not, they’re both blue.
Moreover, PZ himself uses “atheist” in its dictionary sense in citing himself and Rand as dissimilar sorts of atheists—so, in this context at least, it’s obviously neither empty nor useless.
Rather than engage in No True Scotsman arguments over who’s “really” an atheist, why not propose an accurate subcategory marker for the sort of atheist you wish to be perceived to be? (My suggestion: “pedantitheist.”)