gamut

n. total range of notes (Music); entire extent of anything

In color reproduction, including computer graphics and photography, the gamut, or color gamut (pronounced ), is a certain complete subset of colors. The most common usage refers to the subset of colors which can be accurately represented in a given circumstance, such as within a given color space or by a certain output device. Another sense, less frequently used but not less correct, refers to the complete set of colors found within an image at a given time. In this context, digitizing a photograph, converting a digitized image to a different color space, or outputting it to a given medium using a certain output device generally alters its gamut, in the sense that some of the colors in the original are lost in the process.
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Noun
1. a complete extent or range: "a face that expressed a gamut of emotions"
(hypernym) scope, range, reach, orbit, compass, ambit
2. the entire scale of musical notes
(hypernym) scale, musical scale
(classification) music

(n.)
The scale.
  

The gamut of a monitor is the set of colours it can display. There are some colours which can't be made up of a mixture of red, green and blue phosphor emissions and so can't be displayed by any monitor.
[Examples?]
(1994-11-29)