In 1931, the Commission internationale de l’éclairage (International Commission on Illumination or “CIE”), created the CIE 1931 XYZ Color Space. It’s a way of plotting colors by their wavelengths in the visible (to humans) spectrum, and is still in use as the basis for describing (and matching) specific colors when you’re working with, say, ink, or computer screens or digital cameras. It describes about 2.4 million colors, and that number is often used as the “number of colors the human eye can perceive.” When you also take in to account luminosity, though, there may be a lot more.
However many colors the human eye can perceive, the human brain is just not ready for 2.4 million names of colors. The primary ones, like red, green, and blue aren’t generally a problem, and with a bit of practice, many people are able to identify some more, like magenta, cerulean, and azure. Beyond that, what we mostly do is refer to colors as “like this thing I saw.”
Take some of the less-well-known color names, like, say, chartreuse. It’s described as “a pale apple-green” in the dictionary, which is clearly hoping you’ve come into contact with the kind of apples that aren’t red. But even the name itself, “chartreuse,” is just another way of saying “it’s the color of this thing I saw.” In this case, the thing is a liqueur made out of brandy and a bunch of herbs, originally made by (wait for it) the monks of a monastery called “La Grande-Chartreuse.”
“Mauve” is another color name that not everybody knows — it’s some sort of light purple, I’m told. But the name comes from the French word for a particular kind of flower that tends to be, well, some sort of light purple. Again, as I’m told. Although nobody is sure how long that plant has been around, the word “mauve” only entered English around the 1700s, when it began to be used in texts like the Encyclopædia Perthensis of 1796: “The mixture of red and blue produces violet, purple, dove colour, pansey, amaranth, lilac, mauve, and a great number of other shades.” Notice, by the way, that other than red blue and purple, every color on that list is just away of saying “it’s like this thing I saw” — usually, in this case, flowers. They really dropped the ball on the one shade named after a bird; “dove color” really should be simply “dove” by the logic of the rest of the words.
English has a long way to go in naming colors, particularly if we start with the assumption that there are more than two million of them. The most comprehensive list of color words I could find includes only 168 terms — and to get there it had to include pretty rare entries like “badious” (the color of a chestnut), “lateritious” (the color of a red brick), and “porraceous” (the color of a leek). In that last one you can see two inherent limits of our color-naming system. The first is that you have to know what a leek is. And the second is that even if you do know what a leek is (or, you know, have an internet connection), the average leek actually has a number of colors — which one of them is porraceous?.
People who deal with colors all the time and need to be very precise about it have a couple of options. They can use one of several systems like the CIE Color Space — there is the Pantone system, a numeric system of identifying colors (usually colors of ink) named after the Pantone company. There’s the RGB system, which is used in computer software to identify colors, also numerically, based on the individual values of the red, green, and blue pixels used to generate the color on a computer screen. There are some other color specification systems too, but all of them require a certain investment in time and effort to learn. Failing that, the rest of us are just going to have to get better at saying things like “does this shirt look good in smalt, or do you like the watchet one better?”
