<p><strong>Noun</strong></p><ul><li>(Chemistry):<ul><li>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.</li><li>Used chiefly in the manufacture of ammonia, nitric acid, cyanide, explosives, fertilizer, dyes, as a cooling agent, etc.</li><li>Symbol: N</li><li>Atomic number: 7</li><li>Atomic weight: 14.0067</li><li>Density: 1.2506 grams/liter at 0°C and 760 millimeters pressure.</li></ul></li></ul>