Atmosphere (&unr_;), n. [Gr. &unr_; vapor (akin to Skr. ātman breath, soul, G. athem breath) + &unr_; sphere: cf. F. atmosphère. See Sphere.] 1. (Physics) (a) The whole mass of aëriform fluid surrounding the earth; -- applied also to the gaseous envelope of any celestial orb, or other body; as, the atmosphere of Mars. (b) Any gaseous envelope or medium.
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An atmosphere of cold oxygen. Miller.
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2. A supposed medium around various bodies; as, electrical atmosphere, a medium formerly supposed to surround electrical bodies. Franklin.
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3. The pressure or weight of the air at the sea level, on a unit of surface, or about 14.7 lbs. to the sq. inch.
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Hydrogen was liquefied under a pressure of 650 atmospheres. Lubbock.
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4. Any surrounding or pervading influence or condition.
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The chillest of social atmospheres. Hawthorne.
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5. The portion of air in any locality, or affected by a special physical or sanitary condition; as, the atmosphere of the room; a moist or noxious atmosphere.
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