noise

background ack"ground`, n. [Back, a. + ground.] [1913 Webster] 1. Ground in the rear or behind, or in the distance, as opposed to the {foreground}, or the ground in front. [1913 Webster]

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

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

I fancy there was a background of grinding and waiting before Miss Torry could produce this highly finished . . . performance. --Mrs. Alexander. [1913 Webster]

A husband somewhere in the background. --Thackeray. [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. (Science) 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. Specifically: (Physics) Electronic noise present in a system using electronic measuring instrument or in a telecommunications system, which may hide and which must be differentiated from the desired signal; also called background noise or {noise}. [PJC]

8. (Journalism) 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]

{To place in the background}, to make of little consequence.

{To keep in the background}, to remain unobtrusive, inconspicuous or out of sight; -- of people.

{deep background}, (Journalism) the status of an interview which must not be quoted in a publication, even without attribution. Compare {background}[8]. [1913 Webster +PJC]