adjective.
Having a normal oxygen concentration; typically 20-21% in the atmosphere, or 2-3% in physiological contexts.
adjective.
Describing a breathing gas mixture that contains 21% oxygen.
Word Usage
"Koudinavo, N, et al. Alzheimer's abetal2-40 peptide modulates lipid synthesis in neuronal cultures and intact rat fetal brain under normoxic and oxidative stress conditions."