Background \Back"ground`\, n. [Back, a. + ground.]

1. Ground in the rear or behind, or in the distance, as opposed to the foreground, or the ground in front.

2. (Paint.) The space which is behind and subordinate to a portrait or group of figures.

Note: The distance in a picture is usually divided into foreground, middle distance, and background. --Fairholt.

3. Anything behind, serving as a foil; as, the statue had a background of red hangings.

4. A place in obscurity or retirement, or out of sight.

I fancy there was a background of grinding and waiting before Miss Torry could produce this highly finished . . . performance. --Mrs. Alexander.

A husband somewhere in the background. --Thackeray.

Source: Webster's Revised Unabridged Dictionary (1913)