Grue is a fascinating concept and it's much more pervasive than Japanese: https://en.m.wikipedia.org/wiki/Blue%E2%80%93green_distinction_in_language https://en.

Grue is a fascinating concept and it's much more pervasive than Japanese: https://en.m.wikipedia.org/wiki/Blue%E2%80%93green_distinction_in_language https://en.m.wikipedia.org/wiki/Blue%E2%80%93green_distincti... Especially the fact that it tends to impact the speakers ability to perceive shades of the color.