They did have words for those colors. Ancient greek glaukós meant a light blue, khlōrós meant bright green, and kuanós meant a dark blue or green. Of course the

They did have words for those colors. Ancient greek glaukós meant a light blue, khlōrós meant bright green, and kuanós meant a dark blue or green. Of course these words covered a range of potential color values - glaukós could be anything from a blue-grey to a turquoise, khlōrós could cover shades of "green" all the way to an acid yellow. This isn't something special about ancient greek. Even in several modern languages like Japanese, the word for blue also applies to colors that in english would be described as shades of green. The color spectrum is continuous, and where a culture decides to delineate one color from another is arbitrary. For example I would call rgb 60,220,240 a sky blue, while 60,240,220 would be a mint green, but these colors are way closer to one another than either is to rgb 0,255,0 or 0,0,255, which I could just as easily call dark mint or dusk sky. And it's not like english is even the most extreme example. In english, cyan is a shade of blue, for example russian has 7 primary colors, with what we'd call blue split up into a light azure (goluboy) and an ultramarine (siniy). It would be absurd to say that english speakers can't see these colors simply because we refer to both of them as blue.