background -- (a person's social heritage: previous experience or training; "he is a lawyer with a sports background")
background, ground -- (the part of a scene (or picture) that lies behind objects in the foreground; "he posed her against a background of rolling hills")
background, background knowledge -- (information that is essential to understanding a situation or problem; "the embassy filled him in on the background of the incident")
background, background signal -- (extraneous signals that can be confused with the phenomenon to be observed or measured; "they got a bad connection and could hardly hear one another over the background signals")
background -- (relatively unimportant or inconspicuous accompanying situation; "when the rain came he could hear the sound of thunder in the background")
setting, background, scope -- (the state of the environment in which a situation exists; "you can't do that in a university setting")
background, desktop, screen background -- ((computer science) the area of the screen in graphical user interfaces against which icons and windows appear)