Em‐pyr″e‐al (?), a. [L. empyrius, empyreus, fiery, Gr. �, �, in fire, fiery; � in + � fire. See In, and Fire.] Formed of pure fire or light; refined beyond aërial substance; pertaining to the highest and purest region of heaven.
Go, soar with Plato to the empyreal sphere. Pope.
Empyreal air, oxygen gas.