noun
oxygen
OK-sihd-zhuhn
noun
1
A colourless, odourless gas that makes up about a fifth of the air and is essential for humans and animals to breathe.
"Plants release oxygen into the atmosphere during photosynthesis."
"The climbers carried tanks of oxygen for the final ascent."
2
Figuratively, the conditions that let something grow or survive.
"Media attention gave the campaign the oxygen it needed to spread."
How to Use Oxygen
Learner’s notesIn plain EnglishThe gas in the air that living things need to breathe, and figuratively, whatever fuels something's survival or growth.
Common pairings
breathe oxygen
oxygen supply
oxygen tank
oxygen levels
Word Forms
oxygens plural
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Plants release _____ into the atmosphere during photosynthesis.
Etymology
Coined in French from Greek roots meaning "sharp/acid" and "birth/producer," because early chemists wrongly believed oxygen was essential to forming all acids.