A plastic or rubber mask through which oxygen may be breathed from a storage tank.

(physics, astronomy) The nucleosynthesis process, subsequent to carbon burning, in which neon disintegrates to oxygen which subsequently fuses to form silicon, phosphorus sulfur and other elements of atomic number up to 40.

a small gas cylinder of oxygen used in mountain climbing or scuba diving etc

a gas cylinder containing oxygen

the amount of extra oxygen required to oxidize lactic acid in the muscles built up during vigorous exercise

biochemical oxygen demand

(chemistry) A binary compound of oxygen and fluorine, OF₂; a powerful oxidizing agent.

(chemistry) Any binary compound of oxygen and fluorine.

(physics, chemistry) A metastable state of molecular oxygen that has a slightly higher energy than normal triplet oxygen, is diamagnetic rather than paramagnetic, and is more chemically reactive.

O₈, ε oxygen