The abundance of elements heavier than helium in stars as a result of nucleosynthesis(noun)
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Use "metallicity" in a sentence
"Globular clusters are further divided into two major groupings known as metallicity found in the stars in the cluster."
"The star has a low metallicity, which is a measure of elements other than hydrogen and helium."
"The sun is mostly hydrogen and helium, but it also has significant traces of heavier elements like oxygen, carbon and iron, a quality astronomers call "metallicity" despite the nonmetallic nature of some of those elements."