oxygen
nounUK /ˈɒksɪd͡ʒən/ · AU, UK, SC /ˈɔksɪd͡ʒən/
Etymology Borrowed from French oxygène (originally in the form principe oxygène, a variant of principe oxigine ‘acidifying principle’, suggested by Lavoisier), from Ancient Greek ὀξύς (oxús, “sharp”) + γένος (génos, “birth”), referring to oxygen's supposed role in the formation of acids. By surface analysis, oxy- + -gen.
The chemical element (symbol O) with an atomic number of 8 and relative atomic mass of 15.9994. It is a colorless and odorless gas. Sometimes called elemental oxygen to distinguish it from molecular oxygen.
- Holonyms: dioxygen, O₂, oxygen (loose sense)
- By molar fraction, calcium oxide contains equal parts calcium and oxygen.
Molecular oxygen (O₂), a colorless, odorless gas at room temperature.
Loose but very common; even in formal use; loose but very common; even in formal use
- Meronym: oxygen (strict sense)
- About 21% of the air you breathe is oxygen.
1 more example
- Oxygen levels on Earth skyrocketed 2.4 billion years ago, when cyanobacteria evolved photosynthesis: the ability to convert water and carbon dioxide into carbohydrates and waste oxygen using solar energy. The evolutionary precursor of photosynthesis is still under debate, and a new study sheds light.2013 September-October, Katie L. Burke, “In the News”, in American Scientist:
Medicine, Sciences A mixture of oxygen and other gases, administered to a patient to help them breathe.
An atom of this element.
- Look first at any structure to see if there is a carbon with two oxygens attached. Hemiacetals, hemiketals, acetals, and ketals are all alike in that regard.2013, Spencer L. Seager, Michael R. Slabaugh, Chemistry for Today: General, Organic, and Biochemistry, page 479:
Figuratively A condition or environment in which something can thrive.
- Silence is the oxygen of shame.
- They hoped to starve the terrorists of the oxygen of publicity.
1 more example
- . I found myself longing for more than two minutes with the girlfriend, the ex-wife, the assistant, the board member, let alone one of the many staff at the house – anyone to de-center a perspective that has already claimed far too much oxygen in the public sphere.2025 June 2, Adrian Horton, “Tech-bro satire Mountainhead is an insufferable disappointment”, in The Guardian, →ISSN:
- Derived terms
85 terms
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