Munsell color system
a system that specifies the relative degrees of the three variables of color: hue (red, yellow, green, blue, and purple), value (lightness), and chroma (strength or departure from neutral) —note e.g., 10YR 6/4 is a color (of soil) whose hue = 10YR, value = 6, and chroma = 4This definition last updated 07/20/2008