At"mos*phere (#), n. [Gr. vapor (akin to Skr. atman breath, soul, G. athem breath) + sphere: cf. F. atmosphere. See Sphere.]
1. Physics (a)
The whole mass of aeriform 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.
© Webster 1913.