Welcome back to "Doggerel," where I ramble on about words and phrases that are misused, abused, or just plain meaningless.
When you get a bunch of self-identifying materialists together to talk about the definition, you can bet that there'll be a lot of talk about nuance (and you'll be getting some of my opinions along with this), but I think we can all agree that woos repeatedly misuse the term. Woos seem to think that we're all like the Auditors of Reality, and that all we see are moving particles and such and are unable to see anything "bigger" or that we don't believe in concepts like justice or love, or whatever.
It's really quite pathetic.
Justice and love exist, but primarily as a large, fuzzily defined collection of electrochemical reactions called "ideas." Just because people like me recognize them as such doesn't make them any less important. In fact, I might go so far as to suggest that they're more important to us because we recognize that there isn't some magic law in the universe that's going to protect them. We can't just sit back and have faith that some big glowy guy in a toga is going to eventually punish the evil and reward the good based on power and authority that came from nowhere. That's why we have to work towards our ideals.
As for seeing nothing but particles and such, well, false dichotomy. Materialism is essentially about getting down to the tiny mechanisms that run everything. Everything (probably) has a cause or collection of causes. We don't ignore things like consciousness, emotions, and so forth: They're subject to science just like everything else. Calling them "supernatural" is just an act of relabeling that doesn't provide any greater understanding. If it exists, it's material. The weirdest thing that could happen is if it's a very different material from a human point of view.
Side note on the Auditors from Discworld: Unlike in the fictional world, I don't see any really big way that life or even human life is "messier" than nonliving things. Anything that's remotely warm has a lot of movement going on. I can also imagine some astronomer coming along and describing how messy Jupiter's weather system is. Life's just another fragile thing in the universe. Acknowledging that makes me glad I'm around to appreciate something so beautiful.