<p><strong>Noun</strong></p><ul><li>the gaseous envelope surrounding the earth; the air.</li><li>a weather balloon rising high into the atmosphere.</li><li>this medium at a given place: the warm, dry atmosphere of the Joshua tree's natural environment.</li><li>the gaseous envelope surrounding a heavenly body: The white ovals seen in Saturn's atmosphere could be intense storms.</li><li>any gaseous envelope or medium: The ether was treated with a sulfate in an atmosphere of coal gas.</li><li>a conventional unit of pressure, the normal pressure of the air at sea level, about 14.7 pounds per square inch (101.3 kilopascals), equal to the pressure exerted by a column of mercury 29.92 inches (760 millimeters) high: atm.</li><li>a surrounding or pervading mood, environment, or influence: an atmosphere of impending war; a very tense atmosphere.</li><li>the dominant mood or emotional tone of a work of art, as of a play or novel: the chilly atmosphere of a ghost story.</li><li>a distinctive quality, as of a place; character: The old part of town has lots of atmosphere.</li><li>the background sound that is present, or would naturally be present, in the location where a recording or broadcast is made, often recorded as a separate track and then mixed; ambient sound.</li></ul><p><strong>Verb</strong></p><ul><li>to give an atmosphere to: The author had cleverly atmosphered the novel for added chills.</li></ul>