We are prone to think of color names in Hebrew as very specific and saturated hues of those colors. When you hear “red” you probably imagine a bright red color like that of a strawberry. In Hebrew, the word “adom” is usually translated as “red.” When we look at instances like the parah adumah or admoni, however, we see the same word being used to describe an orange color (as in the parallel English “redhead”). In fact, the word “adom” is also used to describe the reddish-purple color of wine and the orange color of red lentil soup. The modified word “adamdam” is an interesting contrast, meaning either “reddish” or “very red.” “Adamah”, on the other hand, implies something closer to brown.
The same is true of the word “yarok.” Besides green, “yarok” also denotes greenish-gold, yellow, and pale yellow (as in “yerakon”, the effect of drought on crops and plants). Again, the word “yerakrak” is “greenish” or “very green”. (This and “adamdam” appear to be the two examples of this doubling in color names, and appear together in the parsha of tzara’as.) “Yerek” is broadly “vegetable.” I’m not sure about “techeles” (which obviously has immediate halachic implications), but I suspect there is a similar spectrum there as well. After all, techeles is reminiscent of the sea and sky and imitated by plant-based indigo.
The colors tzahov, katom, segol, etc. in Modern Hebrew are likely borrowed from objects displaying those frequencies. In the Torah, though, there are three main colors (excluding white). Hebrew has three defining categories for the entire spectrum of visible light, and these categories ultimately correspond to three categories of existence as manifest in these colors.
Although this changes nothing about the way individual colors look, it does change our perception of them. It redefines how we see the interactions between colors. It also changes how we think about color in general. Attempts have been made to establish connections between frequency and gematria, and speculation about color-characteristics (and what art evokes) continues. Synesthesia is always interesting, and light is related to sound and plenty of other metaphors and neuropsychological processes. Aesthetics is a topic in philosophy. In a purely Jewish aesthetic, then, all of the above and more would be addressed, in part by the objectivity of color. Instead of only seeing separate colors, the Torah sees a spectrum that is alive with interaction between hues and shades. The color wheel becomes a turning cycle in a larger mechanism of perception. Indeed, the halachic significance of “yarok” in the arba minim, the meditation involving techeles in the tzitzis, and the antithesis of Edom to Yisrael all point to a much larger perspective than what modern civilization is accustomed to.
The question of what art is and how we view beauty cannot and should not be answered simplistically.