dioxide

American  

[dahy-ok-sahyd, -sid] / daɪˈɒk saɪd, -sɪd /

noun

Chemistry.

1. an oxide containing two atoms of oxygen, each of which is bonded directly to an atom of a second element, as manganese dioxide, MnO 2 , or nitrogen dioxide, NO 2 .

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dioxide British  

/ daɪˈɒksaɪd /

noun

1. any oxide containing two oxygen atoms per molecule, both of which are bonded to an atom of another element

2. another name for a peroxide

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dioxide Scientific  

/ dī-ŏk′sīd /

1. A compound containing two oxygen atoms per molecule.

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Etymology

Origin of dioxide

First recorded in 1840–50; di- ¹ + oxide

Example Sentences

Each year, more than 275 million tons of it are converted into carbon dioxide, adding to global warming and creating a feedback loop that can intensify climate change.

From Science Daily • Apr. 4, 2026

The leftover carbon dioxide will be stored deep beneath the North Sea in sedimentary bedrock and will gradually mineralize over time.

From The Wall Street Journal • Mar. 26, 2026

Cornell University researchers last year estimated that AI growth could add 24 to 44 million metric tons of carbon dioxide to the atmosphere annually by 2030, unless steps are taken to change course.

From Los Angeles Times • Mar. 23, 2026

However the increase in concentrations of heat-trapping greenhouse gases -- carbon dioxide, methane and nitrous oxide -- "to their highest level in at least 800,000 years" has "upset this equilibrium", the WMO said.

From Barron's • Mar. 23, 2026

Lithium hydroxide was used to absorb the carbon dioxide in our exhaled breath.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins