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 .

---

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

---

dioxide Scientific  

/ dī-ŏk′sīd /

1. A compound containing two oxygen atoms per molecule.

---

Etymology

Origin of dioxide

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

Example Sentences

Stegra expects to produce steel that cuts carbon dioxide emissions by 95% compared to the traditional process.

From The Wall Street Journal • Apr. 14, 2026

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

Catalytic converters turn toxic gases into water vapor and carbon dioxide, making car exhaust fumes less environmentally damaging.

From Los Angeles Times • Apr. 3, 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

“And it’s all because of climate change. Burning fossil fuels puts carbon dioxide in the atmosphere, which traps the earth’s heat.”

From "Two Degrees" by Alan Gratz