carbon

noun

car·​bon ˈkär-bən 

plural carbons

1

a

: a nonmetallic chemical element with atomic number 6 that readily forms compounds with many other elements and is a constituent of organic compounds in all known living tissues

—often used before another noun

carbon atoms

carbon life forms

carbon fibers

see Chemical Elements Table

b

: carbon dioxide

Forests, plants and natural lands can help absorb and store excess carbon from the atmosphere.

—Alex Baumhardt

—often used before another noun

carbon emissions

Oil companies … are investing in carbon capture projects as public and investor pressures mount over climate change.

—Paul Takahashi

2

: a carbon rod used in an arc lamp

3

a

: a sheet of carbon paper

b

: carbon copy

Synonyms of carbon

• twin
• image
• replica
• clone
• picture
• duplicate
• portrait
• double

Examples of carbon in a Sentence

a carbon of the document

this new digital camera is a carbon of a well-known model costing almost twice as much

Recent Examples on the Web

The partnership resulted in the implementation of energy efficiency measures across the HVAC and lighting systems that are projected to reduce carbon emissions by an amount equivalent to avoiding the import of approximately 7,200 barrels of oil. —Condé Nast, Condé Nast Traveler, 4 June 2026

Unlike standard carbon filters, these molecular cages force PFAS molecules to clump together inside a cavity, achieving a 98 percent removal rate. —Arthur Zaczkiewicz, Footwear News, 3 June 2026

That’s according to a new report from the United Nations University Institute for Water, Environment and Health (UNU-INWEH) which quantifies the carbon, water, and land footprints of AI's electricity use around the globe. —Simmone Shah, Time, 3 June 2026

The plant will play a significant role in supplying low-carbon power to support economic growth while contributing to China’s environmental and climate objectives. —Prabhat Ranjan Mishra, Interesting Engineering, 3 June 2026

Word History

Etymology

French carbone, from Latin carbon-, carbo ember, charcoal

First Known Use

1788, in the meaning defined at sense 1a

Phrases Containing carbon

• activated carbon
• blind carbon copy
• carbon black
• carbon capture
• carbon capture and storage
• carbon copy
• carbon cycle
• carbon dating
• carbon dioxide
• carbon disulfide
• carbon fiber
• carbon footprint
• carbon monoxide
• carbon paper
• carbon sequestration
• carbon sink
• carbon steel
• carbon tetrachloride

Rhymes for carbon

• fluorocarbon
• hydrocarbon
• radiocarbon

Kids Definition

carbon

noun

car·​bon ˈkär-bən 

1

: a nonmetallic element found more or less pure in nature (as in diamond and graphite) or as a part of coal and petroleum and of the bodies of living things or obtained artificially see element

2

a

: a sheet of carbon paper

b

: carbon copy sense 1

Medical Definition

carbon

noun

car·​bon ˈkär-bən 

: a nonmetallic chemical element with atomic number 6 that readily forms compounds with many other elements and is a constituent of organic compounds in all known living tissues

—symbol C see Chemical Elements Table