http://people.csail.mit.edu/jaffer/Color/CNS-syntax

The BNF Syntax Of CNS

T. Berk, L. Brownston, and A. Kaufman,
A New Color-Naming System for Graphics Languages
IEEE Computer Graphics and Applications, Vol. 2, No. 3 (May, 1982), pages 37-44.

<color name>	`::=`	<achromatic name> \| <chromatic name>
<achromatic name>	`::=`	[<lightness>] gray \| black \| white
<chromatic name>	`::=`	<lightness> <saturation> <hue> \| [<saturation>] [<lightness>] <hue>
<lightness>	`::=`	very dark \| dark \| medium \| light \| very light
<saturation>	`::=`	grayish \| moderate \| strong \| vivid
<hue>	`::=`	<generic hue> \| <halfway hue> \| <quarterway hue>
<generic hue>	`::=`	red \| orange \| brown \| yellow \| green \| blue \| purple
<halfway hue>	`::=`	<generic hue> - <generic hue>
<quarterway hue>	`::=`	<ish form> <generic hue>
<ish form>	`::=`	reddish \| orangish \| brownish \| yellowish \| greenish \| bluish \| purplish

Notes:

If <lightness> is omitted, medium is assumed.
If <saturation> is omitted, vivid is assumed.
<halfway hue> and <quarterway hue> define intermediate hues between two adjacent generic hues around the hue cicrcle shown in Figure 3 of the article. The complete list of hue names is:
- red
- orangish red (brownish red)
- red-orange or orange-red (red-brown or brown-red)
- reddish orange (reddish brown)
- orange (brown)
- yellowish orange (yellowish brown)
- orange-yellow or yellow-orange (brown-yellow or yellow-brown)
- orangish yellow (brownish yellow)
- yellow
- greenish yellow
- yellow-green or green-yellow
- yellowish green
- green
- bluish green
- green-blue or blue-green
- greenish blue
- blue
- purplish blue
- blue-purple or purple-blue
- bluish purple
- purple
- reddish purple
- purple-red or red-purple
- purplish red

The syntax of CNS is orthogonal with respect to the three terms of a color specification. All possible combinations are syntactically correct, although some syntactically correct combinations may not be realizable. For example, if a color is very light or very dark, it cannot be fully saturated. Only colors of intermediate lightness can be vivid. The maximum possible saturation of a color decreases as it becomes light or dark.

Color Dictionaries

Go Figure!