In article ,
"John Zinni" writes:
When an astronomer/astrophysicist uses the word "metals" he/she is referring
to the group of all elements other than H and He.

That would be my first thought, but I might decide otherwise in some
particular context.

Sorry... can't help with the etymology. I'd expect it to be fairly
recent, though, because only in the 1930's was it realized that the
Universe is mostly hydrogen and helium.

--
Steve Willner Phone 617-495-7123
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