oxygen

1. The chemical element (symbol O) with an atomic number of 8 and relative atomic mass of 15.9994. It is a colorless and odorless gas. Sometimes called elemental oxygen to distinguish it from molecular oxygen. (countable, uncountable) · Holonyms: dioxygen, O₂, oxygen (loose sense)· By molar fraction, calcium oxide contains equal parts calcium and oxygen.
2. Molecular oxygen (O₂), a colorless, odorless gas at room temperature. (countable, uncountable) · Meronym: oxygen (strict sense)· About 21% of the air you breathe is oxygen.
3. A mixture of oxygen and other gases, administered to a patient to help them breathe. (countable, uncountable)
4. An atom of this element. (countable)
5. A condition or environment in which something can thrive. (countable, figuratively, uncountable) · Silence is the oxygen of shame.· They hoped to starve the terrorists of the oxygen of publicity.

Plural oxygens