carbon dioxide

noun

: a heavy colorless gas CO2 that does not support combustion, dissolves in water to form carbonic acid, is formed especially in animal respiration and in the decay or combustion of animal and vegetable matter, is absorbed from the air by plants in photosynthesis, and is used in the carbonation of beverages

Examples of carbon dioxide in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Green steel is a crude steel product that emits less carbon dioxide than traditional steelmaking. Maya Wilkins, Chicago Tribune, 28 Feb. 2025 This month, a new kind of space telescope is setting out on a two-year mission to create four complete maps of the entire celestial sky that will catalog the origins of the universe and seek out the ingredients of life − chiefly water and carbon dioxide molecules − in distant interstellar clouds. Stephen J. Beard, USA TODAY, 24 Feb. 2025 Heavy-duty transportation in California is estimated to emit as much carbon dioxide, the main cause of climate change, annually as New Zealand. Peter Eavis, New York Times, 17 Feb. 2025 Payless Power assumed that teams traveling more than 250 miles were flying rather than traveling by bus, with flights producing 0.024 metric tons of carbon dioxide per mile. Sammy Roth, Los Angeles Times, 13 Feb. 2025 See All Example Sentences for carbon dioxide

Word History

First Known Use

1867, in the meaning defined above

Time Traveler
The first known use of carbon dioxide was in 1867

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Cite this Entry

“Carbon dioxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%20dioxide. Accessed 13 Mar. 2025.

Kids Definition

carbon dioxide

noun
: a heavy colorless gas CO2 that is formed especially by the burning and breaking down of organic substances (as in animal respiration), is absorbed from the air by plants in photosynthesis, and has many industrial uses

Medical Definition

carbon dioxide

noun
: a heavy colorless gas CO2 that does not support combustion, dissolves in water to form carbonic acid, is formed especially in animal respiration and in the decay or combustion of animal and vegetable matter, is absorbed from the air by plants in photosynthesis, and is used in the carbonation of beverages

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