A chemical element with symbol O and atomic number 8, essential for respiration in most living organisms and a major component of the Earth's atmosphere.

Plants release oxygen into the atmosphere during photosynthesis.

A colorless, odorless reactive gas that is life-supporting in the air, forming about 21 percent of the Earth's atmosphere.

Divers carry tanks of compressed oxygen to breathe underwater.

A substance that is regarded as providing a vital or essential element to a particular situation or activity.

The new policy acted as oxygen for the struggling economy.

oxygenadjective

Relating to, containing, or supplying oxygen.

The diver put on an oxygen mask before descending.