As long as we're being pedantic nerds: dark matter is not "anything not emitting visible light", although such matter is "dark" in common parlance. Dark matter is called dark because it does not interact electromagnetically at all. No direct interaction with x-rays, radio waves, visible light, UV, IR, etc. etc. etc. It may interact indirectly (eg. by gravitationally distorting spacetime).
Yeah, yeah, I get it. And I still say that's a non-explanation with a misleading name.
There's no proof of material at all, thus not matter, thus no such thing as dark matter. I'd willingly accept other names such as Dark Question Marks. Or maybe Dark Mathematical Terms Yet To Be Named.
Here's a good one: Dark Unobservable Numerically Challenged Entities.
As I said above to another commenter, if you can explain all the observational signatures https://en.wikipedia.org/wiki/Dark_matter#Observational_evid... in another way, you should write a paper! If you don't consider all that observational evidence reliable (which maybe you do not, based on your DUNCE name) and will only be satisfied by direct detection experiments on Earth, well, I don't know what to say to you except that lots of things whose existence was deduced from observational astronomy but not from evidence on Earth panned out, including such simple things as Helium.
The point being that Dark Matter doesn't even seem to interact with matter, so why call it any kind of matter.
Matter isn't matter unless collisions prove it's occupancy of space. That's pretty much why matter is considered anything at all. You can't gloss over a significant lack of collisions.
