atmosphere

noun6

1. •
   The gases surrounding the Earth or any astronomical body.

   • To most people, the huge ice sheets of Antarctica and Greenland are merely water that once was snow. To glaciologists and climatologists, they are storehouses of the Earth's former atmospheres. — 1988
2. •
   (figurative) a mood that seems to fill a place, which the people there can feel

   • The atmosphere for the football match was great.
3. •
   (figurative) The conditions (such as music, illumination, etc.) that can influence the mood felt in an environment.
4. •
   The air in a particular place.

   • The last hue of crimson had died away in the west, and the depth of the rich purple atmosphere was unbroken. — 1834
5. •
   A unit of measurement for pressure equal to 101325 Pa (symbol: atm), approximately the atmospheric pressure at sea level.
6. •
   Extras in a scene who have no spoken lines.

   • Central Casting is in the business of extras, also known as atmosphere or background actors […] — 2006