ELI5: What is a metal?

SPOILERS for Jan. 26, 2025 NYT Strands puzzle! . . . .

Today's NYT Strands puzzle has me fucked up. It was "Pure Metals" and included metals like Aluminum and Cobalt. Fair enough. But then I was like what's the difference between a pure metal and other metals, and then... apparently every element on the periodic table is some kind of metal, metal alloy, etc? Like uranium is just a radioactive metal?

I truly don't remember this from high school, and Wiki hole was getting overwhelming. The word "metal" has lost all meaning.

So l guess my question is. If it's not a gas, is every element on the periodic table some kind of metal? What are non-metals?