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

Mosquito antennae can detect carbon dioxide trails from up to 120 feet (40 yards) away, per USA Today. —Ryan Brennan may 1, Fort Worth Star-Telegram, 1 May 2026

The new findings agree with previous observations that found a high abundance of carbon dioxide within the interstellar comet, also consistent with an object that formed in the outer part of a protoplanetary disk. —Ashley Strickland, CNN Money, 1 May 2026

What attracts mosquitoes more reliably than blood type is carbon dioxide. —Ryan Brennan may 1, Sacbee.com, 1 May 2026

As Earth’s tectonic plates shifted, huge volumes of volcanic gas and carbon dioxide transformed the atmosphere, sucking oxygen out of the oceans and devastating shallow-water environments. —Marlowe Starling, Quanta Magazine, 1 May 2026

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