To be yet more pedantic, it's the only fully-saturated color that's not present in the rainbow.
Colors are perceptual phenomena- the interpretation of a spectrum of light impinging on a patch of retina that almost invariably contains more than one frequency at a time. Colors include white, black, gray, pink, tan, beige, baby blue- none of which are in the rainbow.
How do I read more about this "not being in the rainbow" aspect of this color ?
Wikipedia[1] has nothing to say about it ... in fact, the wiki definition of "fuchsia and magenta are exactly the same color, made by mixing blue and red light at full and equal intensity" makes it seem not that interesting at all ...
>How do I read more about this "not being in the rainbow" aspect of this color ?
By a color "not being in the rainbow" we mean that if you take light and spatially separate its different frequencies (like what happens in a prism or droplet of water), none of those individual frequencies will produce that given color response. And no, it's not that interesting. Almost all color perception experiences involve stimulating a patch of retina with multiple frequencies; we've given names to many of those experiences.
A way that I have had the idea of this explained is this. There are two ways to experience most colours.
Take yellow. You could experience yellow by seeing pure yellow light which is at the yellow wavelength. The other way to experience yellow is by seeing a mixture of red and green wavelength light.
Your eye can't tell the difference between these two types of yellow. The yellow as reflected off a banana is "real" yellow. The yellow you see coming out of your computer monitor is actually just a mix of red and green.
Magenta is interesting because the only way to experience it is by a combinations blue and red. There is no "real" magenta.
I don't understand why a single wavelength would be considered the "real" stimulus that results in a color perception while other metamers for that perception are somehow less "real".
Colors are perceptual phenomena- the interpretation of a spectrum of light impinging on a patch of retina that almost invariably contains more than one frequency at a time. Colors include white, black, gray, pink, tan, beige, baby blue- none of which are in the rainbow.