Dic: in the background, background

in the background:

5. = in the distance

• I kept hearing applause in the background.

6. = behind the scenes, unnoticed, out of the limelight, out of the spotlight

• Rosemary likes to stay in the background.

..... Collins Thesaurus

background: n.2.

a. an inconspicuous or unobtrusive position (esp in the phrase in the background)

b. (as modifier) a background influence

.... Collins
http://www.thefreedictionary.com/background