What this variation seems to imply is that in Proto-Semitic the root y-r-k meant both vegetation and the color of vegetation, ranging from dark green to yellow to pale brown. As time progressed each language developed different distinctions, giving specific meanings to the root and to the words derived from it.Related: The Wine-Dark Sea: Color and Perception in the Ancient World (Erin Hoffman, Clarksworld). Excerpt:
In the case of Biblical Hebrew, we can find the yarok only once: “The range of the mountains is his pasture, and he searcheth after every green thing.” (Job 39:8) and though the King James translator translated the word as “green thing” - it is generally believed that the word in this case was a noun meaning vegetable or vegetation.
This suggests the possibility that not only did Homer lack a word for what we know as “blue”—he might never have perceived the color itself. To him, the sky really was bronze, and the sea really was the same color as wine. And because he lacked the concept “blue”—therefore its perception—to him it was invisible, nonexistent. This notion of concepts and language limiting cognitive perception is called linguistic relativism, and is typically used to describe the ways in which various cultures can have difficulty recalling or retaining information about objects or concepts for which they lack identifying language. Very simply: if we don’t have a word for it, we tend to forget it, or sometimes not perceive it at all.