noun /hju/
A great chocolate-coloured pall lowered over heaven, but the wind was continually charging and routing these embattled vapours; so that as the cab crawled from street to street, Mr. Utterson beheld a marvelous number of degrees and hues of twilight; for here it would be dark like the back-end of evening; and there would be a glow of a rich, lurid brown, like the light of some strange conflagration; and here, for a moment, the fog would be quite broken up, and a haggard shaft of daylight would glance in between the swirling wreaths.
b) The characteristic related to the light frequency that appears in the color, for instance red, yellow, green, cyan, blue or magenta.
In digital arts, HSV color uses hue together with saturation and value.
Wikipedia foundation.