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

It brings nutrients from the deep ocean up to the surface, supporting marine life, and carries carbon dioxide downward where it can be stored long-term.

From Science Daily • Apr. 22, 2026

A government source told the BBC it was planning for a worst case scenario, which would involve the continued closure of the strait and breakdowns in the domestic supply of carbon dioxide.

From BBC • Apr. 16, 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

One of the most abundant organisms on Earth, algae captures carbon dioxide through photosynthesis and yields oil that theoretically could be used to make transportation fuel.

From The Wall Street Journal • Mar. 31, 2026

Its air is thin, containing mostly carbon dioxide but also some molecular nitrogen and argon and very small quantities of water vapor, oxygen and ozone.

From "Cosmos" by Carl Sagan