carbon

American  

[kahr-buhn] / ˈkɑr bən /

noun

1. Chemistry. a widely distributed element that forms organic compounds in combination with hydrogen, oxygen, etc., and that occurs in a pure state as diamond and graphite, and in an impure state as charcoal. C; 12.011; 6; (of diamond) 3.51 at 20°C; (of graphite) 2.26 at 20°C.

2. carbon dioxide or other carbon compounds that are emitted into the atmosphere and cause rising temperatures.

   the carbon produced by burning fossil fuels.

3. carbon copy.

4. a sheet of carbon paper.

5. Electricity.

   1. the carbon rod through which current is conducted between the electrode holder and the arc in carbon arc lighting or welding.

   2. the rod or plate, composed in part of carbon, used in batteries.

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adjective

1. pertaining to or noting the element carbon or any of its compounds, especially carbon dioxide.

   to reduce carbon emissions.

carbon British  

/ ˈkɑːbən /

noun

1. 1. a nonmetallic element existing in the three crystalline forms: graphite, diamond, and buckminsterfullerene: occurring in carbon dioxide, coal, oil, and all organic compounds. The isotope carbon-12 has been adopted as the standard for atomic wt; carbon-14 , a radioisotope with a half-life of 5700 years, is used in radiocarbon dating and as a tracer. Symbol: C; atomic no: 6; atomic wt: 12.011; valency: 2, 3, or 4; relative density: 1.8–2.1 (amorphous), 1.9–2.3 (graphite), 3.15–3.53 (diamond); sublimes at 3367±25°C; boiling pt: 4827°C

   2. ( as modifier )

      a carbon compound

2. short for carbon paper carbon copy

3. a carbon electrode used in a carbon-arc light or in carbon-arc welding

4. a rod or plate, made of carbon, used in some types of battery

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carbon Scientific  

/ kär′bən /

1. A naturally abundant, nonmetallic element that occurs in all organic compounds and can be found in all known forms of life. Diamonds and graphite are pure forms, and carbon is a major constituent of coal, petroleum, and natural gas. Carbon generally forms four covalent bonds with other atoms in larger molecules. Atomic number 6; atomic weight 12.011; sublimation point above 3,500°C; boiling point 4,827°C; specific gravity of amorphous carbon 1.8 to 2.1, of diamond 3.15 to 3.53, of graphite 1.9 to 2.3; valence 2, 3, 4.

2. See Periodic Table

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carbon Cultural  

1. A chemical element; its symbol is C. The carbon nucleus has six protons and six or more neutrons; six electrons are in orbit around the carbon nucleus. (See hydrocarbons and organic molecules (see also organic molecule).)

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Discover More

Carbon forms the basis for all living tissue.

Other Word Forms

• carbonless adjective
• carbonous adjective
• noncarbon noun

Etymology

Origin of carbon

1780–90; < French carbone, coinage based on Latin carbōn- (stem of carbō ) charcoal

Explanation

Carbon is an element that takes the solid form of either graphite or diamond. Carbon is one of the basic elements of any living thing. Carbon is known as the most essential element for life, and it's the second most abundant — after oxygen — in the human body. Carbon paper was an early method of making copies, using a sheet of paper coated with wax and, originally, carbon soot. The copy that results from writing or typing on paper that's placed on top, with a blank page beneath the carbon paper, is called a carbon copy. The Latin root of carbon is carbonem, "charcoal."

Example Sentences

We have also known since the first annual UK-EU summit 11 months ago that the UK is negotiating deals with the EU on food and drink standards, carbon emissions and electricity.

From BBC • Apr. 13, 2026

Between 2007 and 2010, Africa's forests were gaining carbon.

From Science Daily • Apr. 13, 2026

At the center of the discovery is a carbene, a form of carbon with just six valence electrons.

From Science Daily • Apr. 11, 2026

Unwanted gas can be burned, releasing carbon dioxide, or even simply vented.

From The Wall Street Journal • Apr. 9, 2026

Lots of carbon comes up with kimberlite ejecta, but most is vaporized or turns to graphite.

From "A Short History of Nearly Everything" by Bill Bryson

Related Words

• graphite
• soot