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> organic ices – such as frozen carbon dioxide

I'm pretty sure that CO2 isn't classified as organic.

Organic has a specific meaning in chemistry: https://en.m.wikipedia.org/wiki/Organic_chemistry

Yes but in some cases, astronomy uses slightly different definitions of key scientific terms: "metal", for example, means anything other than hydrogen or helium.

Nonsense. Nickel-iron asteroids are called "metallic," because they're largely made out of, well, metal. Stony asteroids are called "carbonaceous" because they've got a lot of carbon. They're very definitely not called "metal". And astronomers believe that the core of Jupiter is both hydrogen and metallic -- hydrogen compressed to the point where it acquires the property of a metal.

So: there are many things that are neither hydrogen nor helium nor metal, and a few things which are both hydrogen and metal.

I think GP meant "metallicity" as a property of stellar objects:

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

"Organic" as chiefly of biological origin? Yeah.

"Organic" as occurs in nature and beneficial for plants? Sure.

"Organic" as compound containing carbon? Yes.

"Organic" as compound with at least one carbon-hydrogen bond? Nope.

"Organic" as a compound with a significant number of carbon atoms? Nope.

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