monoatomic

/ˌmɑnoʊəˈtɑmɪk/
adjective
  1. Consisting of a single atom; used to describe a gas or element whose particles are individual atoms rather than molecules.
    • Helium is a monoatomic gas, meaning each particle is just one atom.
    • Monoatomic ions like sodium (Na+) are common in chemistry.
    • Noble gases such as neon exist in a monoatomic form.
What does "monoatomic" mean? | whatsthatwordmean | whatsthatwordmean