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.
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(1994-11-29)
GAMUT
Meaning of GAMUT in English
FOLDOC computer English dictionary. Английский словарь по компьютерам FOLDOC. 2012