The dictionary entry for the word chroma says, "the purity of a color, or its freedom from white or gray."
What does that statement mean? What is color made of? What causes color?
I was reading this link and my interpretation, in the most lay terms, is that color is caused because and when the light that reaches our eye is different from the light that was discharged from a light-source.
This could happen due to:
1) Some of the light being absorbed on its way to our eye; or 2) Only a selected/filtered band of frequency/wave-length of light rays reaching our eye out of the whole spectrum that was discharged from the light-source; 3) Other reasons, which are more or less variations of the single most important fact that color is created because of a variation in the amount or intensity of light that reaches our eye.
Is my understanding correct?
What then is the meaning of the phrase, "the purity of a color, or its freedom from white or gray?"