At″mos‐phere (�), n. [Gr. � vapor (akin to Skr. ātman breath, soul, G. athem breath) + � 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.
An atmosphere of cold oxygen.
Miller.
2. A supposed medium around various bodies; as, electrical atmosphere, a medium formerly supposed to surround electrical bodies. Franklin.
3. The pressure or weight of the air at the sea level, on a unit of surface, or about 14.7 Ibs. to the sq. inch.
Hydrogen was liquefied under a pressure of 650 atmospheres.
Lubbock.
4. Any surrounding or pervading influence or condition.
The chillest of social atmospheres.
Hawthorne.
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.