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

These closures reflect various factors, including poor investment returns, a lack of government support for refinery upgrades and higher carbon and energy costs. —Ian King, CNBC, 15 Apr. 2026

More In 2018, Xcel Energy was the first energy company to commit to being 100% carbon free, with plans to build up wind, geothermal, solar, and storage while retiring its coal plants. —Steve Gelsi, semafor.com, 14 Apr. 2026

The deal offered Exelon, now Constellation, the security of reliable income to meet its costs, while ensuring reliable carbon-free energy delivery for northern Illinoisians. —Maggie Dougherty, CBS News, 14 Apr. 2026

This project, a partnership between Rolls-Royce SMR and Great British Energy – Nuclear, aims to advance domestic, low-carbon energy technology. —Mrigakshi Dixit, Interesting Engineering, 14 Apr. 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

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