#1 atmosphere n. [ambiance, ambience] a particular environment or surrounding influence; "there was an atmosphere of excitement". wn
#2 atmosphere n. [standard atmosphere, atm, standard pressure] a unit of pressure: the pressure that will support a column of mercury 760 mm high at sea level and 0 degrees centigrade. wn
#3 atmosphere n. [air] the mass of air surrounding the Earth; "there was great heat as the comet entered the atmosphere"; "it was exposed to the air". wn
#4 atmosphere n. [atmospheric state] the weather or climate at some place; "the atmosphere was thick with fog". wn
#5 atmosphere n. the envelope of gases surrounding any celestial body. wn
vizzz