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

In a triglyceride, there are three fatty acids, each one connected to the same three-carbon glycerol molecule, which acts as the backbone of the molecule. —Rosemary Trout, The Conversation, 10 June 2026

The clay minerals were blended with graphene — a highly conductive, ultra-thin form of carbon. —Mrigakshi Dixit, Interesting Engineering, 10 June 2026

By contrast, solar, wind, geothermal, hydropower and nuclear are carbon-free. —ABC News, 10 June 2026

Yu is a pioneer in studying carbon-hydrogen activation whose work has transformed how chemists build and modify complex molecules, with implications for drug discovery and medical research. —Ashley MacKin Solomon, San Diego Union-Tribune, 9 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