An atmosphere is a surrounding environment or influence. If you and your coworkers talk behind each other's backs, you will create a nasty atmosphere at work.
Atmosphere was coined by 17th-century scientists combining the Greek words for vapor, atmos, and sphere, sphaira. The earth's atmosphere is the air and gas surrounding our planet. Atmosphere also describes the feeling of a place. A coffee shop might have a cool, artsy atmosphere. Some plants grow best in a damp atmosphere. In physics, atmosphere is a unit of pressure equal to the air pressure at sea level.