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

Lim explained that the fluid, unlike carbon or other refining agents, is extremely selective and never comes into contact with the rest of the wine. —Nicola Twilley, New Yorker, 5 Jan. 2026

By keeping more carbon in the final product, the new process not only cuts emissions but also increases yield and ultimately improves its economics. —Christopher McFadden, Interesting Engineering, 4 Jan. 2026

Balance Nitrogen with Carbon Compost requires a balance of green (nitrogen-rich) and brown (carbon-rich) materials to break down, typically 4 parts browns to 1 part greens. —Samantha Johnson, Martha Stewart, 2 Jan. 2026

Furthermore, these systems will provide back-up power for residents during a storm outage, reduce peak capacity on existing utility-scale power plants and reduce carbon pollution. —Bob Norberg, The Orlando Sentinel, 1 Jan. 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