carbon cycle

noun

1
: the cycle of carbon in the earth's ecosystems in which carbon dioxide is fixed by photosynthetic organisms to form organic nutrients and is ultimately restored to the inorganic state (as by respiration, protoplasmic decay, or combustion)
2
: a cycle of thermonuclear reactions in which four hydrogen atoms synthesize into a helium atom by the catalytic action of carbon with the release of nuclear energy and which is held to be the source of most of the energy radiated by the sun and stars

Examples of carbon cycle in a Sentence

Recent Examples on the Web
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These tiny, often overlooked, organisms might not possess the grandeur of whales or the mystique of deep-sea predators, but their role in the ocean’s carbon cycle could be nothing short of monumental. Scott Travers, Forbes, 20 Dec. 2024 The carbon in their corpses — lignin, cellulose, fatty acids, proteins, and so on — feeds microorganisms that break down large molecules and return carbon dioxide to the air, completing the carbon cycle. Umair Irfan, Vox, 7 Dec. 2018 By doing this, the brand is combatting the harms of fast fashion by rebalancing the carbon cycle, improving soil health, protecting watersheds, and supporting American farmer livelihoods. Kelsey Glennon, Travel + Leisure, 1 Dec. 2024 The land turns from a carbon sink into a carbon source, further unbalancing our planet’s carbon cycle. Erik Kobayashi-Solomon, Forbes, 20 Oct. 2024 See all Example Sentences for carbon cycle 

Word History

First Known Use

1901, in the meaning defined at sense 1

Time Traveler
The first known use of carbon cycle was in 1901

Dictionary Entries Near carbon cycle

Cite this Entry

“Carbon cycle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%20cycle. Accessed 26 Dec. 2024.

Kids Definition

carbon cycle

noun
: the cycle of carbon in living things in which carbon dioxide is used in photosynthesis to form food and growth substances and is later returned to the environment by respiration, decay, and burning

Medical Definition

carbon cycle

noun
: the cycle of carbon in living beings in which carbon dioxide is fixed by photosynthesis to form organic nutrients and is ultimately restored to the inorganic state by respiration and protoplasmic decay

More from Merriam-Webster on carbon cycle

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