di·​ox·​ide | \ (ˌ)dī-ˈäk-ˌsīd How to pronounce dioxide (audio) \

Definition of dioxide

: an oxide (such as carbon dioxide) containing two atoms of oxygen in the molecule

Examples of dioxide in a Sentence

Recent Examples on the Web Cement alone accounts for 7% of global carbon-dioxide emissions, according to the International Energy Agency. David Hodari, WSJ, "Bill Gross, 1990s Dotcom Trailblazer, Is Now Betting on Green Energy," 6 Oct. 2020 Temperatures inside rose to uncomfortable levels and kept on rising, to more than a hundred and ten degrees, and carbon-dioxide levels climbed, too. Elizabeth Kolbert, The New Yorker, "The Day Nuclear War Almost Broke Out," 5 Oct. 2020 Merkel pledged to work for a stronger post-pandemic Europe, setting her sights on an investment deal with China and a pact to slash carbon-dioxide emissions by the end of the year. Raymond Colitt, Bloomberg.com, "Merkel Calls for Quick End to Expansive German Debt Spending," 30 Sep. 2020 The announcement came as a surprise, and an important one at that; China is the world’s biggest carbon-dioxide emitter, being responsible for around 28% of all such emissions. David Meyer, Fortune, "Extraordinary stories of business success defy economic downturn," 23 Sep. 2020 For example, one group of ninth graders worked on a research project investigating carbon-dioxide levels in the classrooms of Byng Junior High School. Kristina Rizga, The Atlantic, "Teaching Kids to Love Science," 9 Sep. 2020 Carbon dioxide stays in the air for a century, so its levels in the atmosphere continue to go up, Petteri Taalas, secretary-general of the World Meteorological Organization, told the Associated Press. Irina Ivanova, CBS News, "Greenhouse gas emissions around the world nearly back to pre-pandemic levels," 9 Sep. 2020 Carbon dioxide, an important greenhouse gas contributing to global warming, has increased by 9 percent since 2005 and by 31 percent since 1950. Neelu Tummala, Scientific American, "What Climate Change Does to the Human Body," 29 Aug. 2020 Chlorine dioxide is mostly used to disinfect drinking water supplies and has never been legitimately used or sold for use in or on the human body. Radina Gigova, CNN, "Lawmakers push toxic disinfectant as Covid-19 treatment in Bolivia, against Health Ministry's warnings," 29 July 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dioxide.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of dioxide

circa 1847, in the meaning defined above

History and Etymology for dioxide

International Scientific Vocabulary

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Time Traveler for dioxide

Time Traveler

The first known use of dioxide was circa 1847

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Statistics for dioxide

Last Updated

11 Oct 2020

Cite this Entry

“Dioxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dioxide. Accessed 22 Oct. 2020.

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More Definitions for dioxide


How to pronounce dioxide (audio)

English Language Learners Definition of dioxide

chemistry : a molecule that has two atoms of oxygen and one atom of another element (such as carbon)


di·​ox·​ide | \ (ˈ)dī-ˈäk-ˌsīd How to pronounce dioxide (audio) \

Medical Definition of dioxide

: an oxide (as carbon dioxide) containing two atoms of oxygen in a molecule

More from Merriam-Webster on dioxide

Nglish: Translation of dioxide for Spanish Speakers

Britannica English: Translation of dioxide for Arabic Speakers

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