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

Emissions from Salesforce’s data centers have increased to 244,000 metric tons of carbon-dioxide equivalent in fiscal year 2019 from 149,000 tons in 2017. Sara Castellanos, WSJ, "Tech Executives Spearhead Green Initiatives," 24 June 2019 They were inspired by observations of dark spots in the carbon-dioxide ice caps at the Martian poles, Wordsworth said. Mike Wall, Scientific American, "Silica Blankets Could Make Mars Habitable," 15 July 2019 High-flying airplanes spraying sulphur dioxide into the atmosphere, thereby mimicking gas from volcanoes and reflecting the sun’s heat, could be done safely according to another study in the same issue of Nature Climate Change. Stephen Leahy, National Geographic, "Climate study warns of vanishing safety window—here’s why," 12 Mar. 2019 In a paper published in 2011 Mr Lewis argued that carbon lost to the atmosphere through tree death and fire in the droughts of 2005 and 2010 might offset as much as a decade’s worth of carbon-dioxide absorption by the forest. The Economist, "The Amazon is approaching an irreversible tipping point," 1 Aug. 2019 Certainly, the mass planting of trees on a global scale has the potential to help absorb the carbon-dioxide emissions that drive global warming. The Economist, "Why France’s forests are getting bigger," 18 July 2019 Adding more vehicles to production lines would help gain scale and save costs, and offer Ford a platform to better comply with tougher rules on carbon-dioxide emissions in Europe. Keith Naughton, Fortune, "Volkswagen Joins Ford by Investing Self-Driving Startup Argo AI, Now Worth $7 Billion," 12 July 2019 Thus wind energy now offers great opportunities for lowering carbon-dioxide emissions. Peter R. Orszag, Houston Chronicle, "Guess what’s holding back wind power in the U.S.," 12 July 2019 Commercial reactors have used the same fuel for decades: small pellets of uranium dioxide stacked inside long cylindrical rods made of a zirconium alloy. Mark Fischetti, Scientific American, "Safer Nuclear Reactors Are on the Way," 1 July 2019

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

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Statistics for dioxide

Last Updated

2 Sep 2019

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Time Traveler for dioxide

The first known use of dioxide was circa 1847

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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

Rhyming Dictionary: Words that rhyme with dioxide

Nglish: Translation of dioxide for Spanish Speakers

Britannica English: Translation of dioxide for Arabic Speakers

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formidable, illustrious, or eminent

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