nitrogen

American  

[nahy-truh-juhn] / ˈnaɪ trə dʒən /

noun

Chemistry.

1. a colorless, odorless, gaseous element that constitutes about four-fifths of the volume of the atmosphere and is present in combined form in animal and vegetable tissues, especially in proteins: used chiefly in the manufacture of ammonia, nitric acid, cyanide, explosives, fertilizer, dyes, as a cooling agent, etc. N; 14.0067; 7; density: 1.2506 grams/liter at 0°C and 760 millimeters pressure.

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nitrogen British  

/ ˈnaɪtrədʒən /

noun

1. 1. a colourless odourless relatively unreactive gaseous element that forms 78 per cent (by volume) of the air, occurs in many compounds, and is an essential constituent of proteins and nucleic acids: used in the manufacture of ammonia and other chemicals and as a refrigerant. Symbol: N; atomic no: 7; atomic wt: 14.00674; valency: 3 or 5; density: 1/ 2506 kg/m³; melting pt: –210.00°C; boiling pt: –195.8°C

   2. ( as modifier )

      nitrogen cycle

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nitrogen Scientific  

/ nī′trə-jən /

1. A nonmetallic element that makes up about 78 percent of the atmosphere by volume, occurring as a colorless, odorless gas. It is a component of all proteins, making it essential for life, and it is also found in various minerals. Nitrogen is used to make ammonia, nitric acid, TNT, and fertilizers. Atomic number 7; atomic weight 14.0067; melting point −209.86°C; boiling point −195.8°C; valence 3, 5.

2. See Periodic Table See Note at oxygen

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nitrogen Cultural  

1. A chemical element that makes up about four-fifths of the atmosphere of the Earth. Its symbol is N.

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Discover More

Like carbon, nitrogen is a necessary element in the tissues of living things.

Etymology

Origin of nitrogen

First recorded in 1785–95; from French nitrogène; see origin at nitro-, -gen

Example Sentences

“If we can provide some sort of financing package for a new company to build a new nitrogen production facility, not only do you increase supply, you also increase competition,” he said.

From Salon • May 15, 2026

Although Egypt produces seven to eight million tonnes of nitrogen fertiliser annually and exports more than half, domestic access remains uneven.

From Barron's • May 15, 2026

Anta collaborated with Chinese scientists to develop a type of foam cushion made with nitrogen that provides extra bounciness—all but demolishing Nike’s competitive moat.

From The Wall Street Journal • May 12, 2026

Although many diving species have evolved ways to reduce the risk of 'the bends', nitrogen bubbles can still form in their bloodstream.

From Science Daily • May 9, 2026

When leaves or branches fall, the carbon and nitrogen in the debris are rapidly reabsorbed by the hyperefficient root systems of tropical plants.

From "1491" by Charles C. Mann