"background" - key terms from Wikipedia

additional background vocals
background
background and win means
background check
background checks
background color
background dancer
background extinction rate
background independence
background investigation
background knowledge
background layers
background lights
background material
background music
background noise
background painting
background palette
background performer
background plane
background plate
background radiation
background score
background source
background stars
background vocals
background vocals on half
background vocals on track
background vocals on yellow submarine
background window
best background score
blue background
book as background characters
cosmic background
cosmic background radiation
cosmic microwave background
cosmic microwave background radiation
criminal background
desktop background
faint reply in the background
family background
fictional background
living in the background
natural background radiation
professional background singers
social background
solo and background vocals
used as background music
white background
yellow background