An Etymological Dictionary of Astronomy and Astrophysics

General: That part of a view or scene that serves as a setting for the main objects, persons, etc.
Astro.: The part of an observed field which is not physically related to the objects of interest and lies behind them.

Etymology (EN): Background, from → back + ground, from M.E., from O.E. grund; akin to O.H.G. grunt “ground.”

Etymology (PE): Paszaminé, from pas-, → back, + zaminé “ground,” from zamin “ground,” → earth.

See also: → foreground.