1. The amount of noise in a room without any primary sound. The background noises in a room (HVAC, traffic noise, etc.).
    Source:     Church Audio & Acoustics Glossary
     
  2. All-encompassing sound at a given place, usually a composite of sounds from many sources near and far.
    Source: [http://members.aol.com/inceusa/glossary.html Glossary of Terms in Noise Control Engineering]
     
  3. The composite, all-inclusive sound that is associated with a given environment (usually from many sound sources), excluding the analysis system’s electrical noise and the sound source of interest, which in most cases presented herein is aircraft.
    Source: http://www.volpe.dot.gov/acoustics/docs/1990-1999/1999-1.pdf
     

  4. The composite of airborne sound from many sources near and far associated with a given environment. No particular sound is singled out for interest.
    Source: http://www.owenscorning.com/around/sound/glossary.asp

[[Category: Acoustics]]