The blue-green distinction is interesting because it's different in East Asia:

* https://en.wikipedia.org/wiki/Blue%E2%80%93green_distinction...

The color of a traffic light can be referred to as blue or green. This sometimes leads to interesting translations where the color 青 can be translated as green or blue (eg 青茶 being translated as "blue tea" in Taiwan instead of "greener oolong tea" or something).