1.  background(n = noun.attribute) - a person's social heritage: previous experience or training; "he is a lawyer with a sports background"

2.  background(n = noun.cognition) ground - the part of a scene (or picture) that lies behind objects in the foreground; "he posed her against a background of rolling hills"

3.  background(n = noun.cognition) background knowledge - information that is essential to understanding a situation or problem; "the embassy filled him in on the background of the incident"
Derived form noun backgrounder₁

4.  background(n = noun.event) 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"

5.  background(n = noun.event) - relatively unimportant or inconspicuous accompanying situation; "when the rain came he could hear the sound of thunder in the background"
Derived form verb background₁

6.  background(n = noun.state) scope, setting - the state of the environment in which a situation exists; "you can't do that in a university setting"

7.  background(n = noun.artifact) desktop, screen background - (computer science) the area of the screen in graphical user interfaces against which icons and windows appear;

8.  background(n = noun.artifact) backcloth, backdrop - scenery hung at back of stage;

   background(v = verb.change) downplay, play down - understate the importance or quality of; "he played down his royal ancestry"
Antonym: foreground
Derived form noun background₅
Sample sentences: Somebody ----s something; Something ----s something

1.  Ground in the rear or behind, or in the distance, as opposed to the foreground, or the ground in front. [1913 Webster]

2.  The space which is behind and subordinate to a portrait or group of figures. [1913 Webster]

3.  Anything behind, serving as a foil; as, the statue had a background of red hangings. [1913 Webster]

4.  A place in obscurity or retirement, or out of sight. [1913 Webster]

5.  The set of conditions within which an action takes place, including the social and physical conditions as well as the psychological states of the participants; as, within the background of the massive budget deficits of the 1980's, new spending programs had little chance of passage by the congress. [PJC]

6.  The set of conditions that precede and affect an action, such as the social and historical precedents for the event, as well as the general background{5}; as, against the background of their expulsion by the Serbs, the desire of Kosovars for vengeance is understandable though regrettable. [PJC]

7.  The signals that may be detected by a measurement which are not due to the phenomenon being studied, and tend to make the measurement uncertain to a greater or lesser degree. [PJC]

8.  An agreement between a journalist and an interviewee that the name of the interviewee will not be quoted in any publication, although the substance of the remarks may be reported; -- often used in the phrase “on background”. Compare deep background. [PJC]

background, n.
1 part of a scene, picture, or description, that serves as a setting to the chief figures or objects and foreground.
2 an inconspicuous or obscure position (kept in the background).
3 a person's education, knowledge, or social circumstances.
4 explanatory or contributory information or circumstances.
5 Physics low-intensity ambient radiation from radioisotopes present in the natural environment.
6 Electronics unwanted signals, such as noise in the reception or recording of sound.

Idiom:
background music music intended as an unobtrusive accompaniment to some activity, or to provide atmosphere in a film etc.

N  distance, space, remoteness, farness, far- cry to, longinquity, elongation, offing, background, remote region, removedness, parallax, reach, span, stride, outpost, outskirt, horizon, aphelion, foreign parts, ultima Thule, ne plus ultra, antipodes, long range, giant's stride, dispersion, length, cosmic distance, light-years, distant, far off, far away, remote, telescopic, distal, wide of, stretching to, yon, yonder, ulterior, transmarine, transpontine, transatlantic, transalpine, tramontane, ultramontane, ultramundane, hyperborean, antipodean, inaccessible, out of the way, unapproached, unapproachable, incontiguous, far off, far away, afar, afar off, off, away, a long way off, a great way off, a good way off, wide away, aloof, wide of, clear of, out of the way, out of reach, abroad, yonder, farther, further, beyond, outre mer, over the border, far and wide, over the hills and far away, from pole to pole, to the uttermost parts, to the ends of the earth, out of hearing, nobody knows where, a perte de vue, out of the sphere of, wide of the mark, a far cry to, apart, asunder, wide apart, wide asunder, longo intervallo, at arm's length, distance lends enchantment, it's a long long way to Tipperary, out of sight, out of mind.

N  rear, back, posteriority, rear rank, rear guard, background, hinterland, occiput, nape, chine, heels, tail, rump, croup, buttock, posteriors, backside scut, breech, dorsum, loin, dorsal region, lumbar region, hind quarters, aitchbone, natch, natch bone, stern, poop, afterpart, heelpiece, crupper, wake, train, reverse, other side of the shield, back, rear, hind, hinder, hindmost, hindermost, postern, posterior, dorsal, after, caudal, lumbar, mizzen, tergal, behind, in the rear, in the background, behind one's back, at the heels of, at the tail of, at the back of, back to back, after, aft, abaft, astern, sternmost, aback, rearward, ogni medaglia ha il suo rovescio, the other side of the coin.