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WordReference Random House Learner's Dictionary of American English © 2024ni•tro•gen /ˈnaɪtrədʒən/USA pronunciation n. [uncountable]- Chemistrya colorless, odorless, gaseous element that makes up about four-fifths of the earth's atmosphere and is found in animal and vegetable tissues.
ni•trog•e•nous /naɪˈtrɑdʒənəs/USA pronunciation adj. WordReference Random House Unabridged Dictionary of American English © 2024ni•tro•gen (nī′trə jən),USA pronunciation n. [Chem.]- 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, esp. in proteins: used chiefly in the manufacture of ammonia, nitric acid, cyanide, explosives, fertilizer, dyes, as a cooling agent, etc. Symbol: N;
at. wt.: 14.0067;
at. no.: 7;
density: 1.2506 g/l at 0°C and 760 mm pressure.
- French nitrogène. See nitro-, -gen
- 1785–95
Collins Concise English Dictionary © HarperCollins Publishers:: nitrogen /ˈnaɪtrədʒən/ n - 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
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