ATMOSPHERE

n. layer of gases surrounding the earth; layer of gases surrounding a planet; climate of a particular region; unit of air pressure (Physics); tone or mood of a place or thing

An atmosphere is a layer of gases that may surround a material body of sufficient mass. The gases are attracted by the gravity of the body, and are retained for a longer duration if gravity is high and the atmosphere's temperature is low. Some planets consist mainly of various gases, and thus have very deep atmospheres (see gas giants).
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Atmosphere /at·mos·phere/ 1. the entire gaseous envelope surrounding the earth and subject to the earth's gravitational field. 2. [more]Atmosphere - Community and Resources

Noun
1. a particular environment or surrounding influence; "there was an atmosphere of excitement"
(synonym) ambiance, ambience
(hypernym) condition, status
(hyponym) genius loci
2. a unit of pressure: the pressure that will support a column of mercury 760 mm high at sea level and 0 degrees centigrade
(synonym) standard atmosphere, atm, standard pressure
(hypernym) pressure unit
(hyponym) STP, s.t.p.
3. the mass of air surrounding the Earth; "there was great heat as the comet entered the atmosphere"; "it was exposed to the air"
(synonym) air
(hypernym) region, part
(hyponym) airspace
(part-holonym) Earth, world, globe
(part-meronym) airspace, air space
4. the weather or climate at some place; "the atmosphere was thick with fog"
(synonym) atmospheric state
(hypernym) weather, weather condition, atmospheric condition
(hyponym) air mass
5. the envelope of gases surrounding any celestial body
(hypernym) gas
(part-meronym) exosphere
6. a distinctive but intangible quality surrounding a person or thing; "an air of mystery"; "the house had a neglected air"; "an atmosphere of defeat pervaded the candidate's headquarters"; "the place had an aura of romance"
(synonym) air, aura
(hypernym) quality
(hyponym) mystique

n. atmosphere, ambience; feeling, go; vibes, aura