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

Not a single molecule of carbon dioxide is released during the process. —Michael Franco, New Atlas, 13 Mar. 2025

And how much carbon dioxide emissions, compared to coal? —David Pogue, CBS News, 9 Mar. 2025

Researchers believe these likely depict differences in atmospheric carbon chemistry, such as pockets of carbon monoxide and carbon dioxide. —Andrew Paul, Popular Science, 5 Mar. 2025

Oxygen levels hover between 7% and 10% (compared to 21% in normal air), and carbon dioxide levels are up to 100 times higher than on the surface. —Scott Travers, Forbes, 2 Mar. 2025

Word History

First Known Use

1867, in the meaning defined above

Rhymes for carbon dioxide

• acetamide
• acetonide
• acidified
• antimonide
• beatified
• benzaldehyde
• borohydride
• chalcogenide
• commodified
• decalcified
• declassified
• disaccharide

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