I think the term "market" comes from the fact that it uses stock market–like pricing and allows you to sell your bets at any time. Ie. you buy "shares" of some outcome for 0.3$ if the probability is 30%, and then if the probability at any point goes to 50%, you can sell the "shares" for 0.5$ each.

(Which of course doesn't make it any better or less of a casino, this is just to say that the word market didn't come from nowhere)

That already had a name

https://en.wikipedia.org/wiki/Betting_exchange

sure, a bet market which is gambling, not a 'prediction market'. those are not predictions

You can gamble on the stock exchange, just like you can "non-gamblingly" hedge certain risks by buying/selling certain financial products such as event futures. (Many insurance policies are structurally just that and are used for very boring non-gambling purposes!)

I don't think you'll find a simple/useful answer by slicing the problem on that axis.

At least when I put money in the stock market, I own a piece of the companies I'm invested in. I get some small amount of voting rights.

You don't get anything outside of winnings or losses from your bets on a "prediction market".

Sure, but most retail shareholders don’t make use of that right, and it’s severely diluted compared to preferred shares to boot.

That’s what I mean: Many things can be used in very different ways. These incentives usually matter more than the underlying things in finance.

That's just gambling with frills.

> they are not being sold by people.

I think you might be mistaken about how Polymarket works. They are indeed only a platform operator; all trades are directly between participants.