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

They found that the 2026 games will generate over 9 million tons of carbon dioxide, about double the average for the last four World Cups — 4.7 million tons.

From Los Angeles Times • May 18, 2026

A sewage plant is basically a farm for microorganisms that break down poop, releasing carbon dioxide in the process.

From The Wall Street Journal • May 14, 2026

Despite more knowledge and awareness of the effects of pollution, the presence of nitrogen dioxide and other pollutants has reduced both in the long-term and in recent years.

From BBC • May 13, 2026

It’s one of the nation’s largest sources of sulfur dioxide, which forms haze and harms the respiratory system, and the second-largest source of carbon dioxide, according to EPA data.

From Salon • May 10, 2026

The very thin and tenuous atmosphere of Io was found by Voyager to be composed mainly of sulfur dioxide.

From "Cosmos" by Carl Sagan