Why do they call “blue traffic light” in Japan?

Do you know why “green light” is called “blue light” in Japan? It is obvious that the color is green, and *Japanese people also acknowledge that, so they also consider it a green color. But when talking about traffic lights, it’s called blue. Before, Japanese only had these 4 colors, and they are still the basic color terms in Japan. For this reason, they had much wider meanings 

“Black”… dark colors in general

“White”… clear colors in general

“Red”… bright colors in general

“Blue”… unclear colors in general


As they are shown above, “blue” used to be used to indicate many colors including green.For example, Japanese has some expressions using “blue” which indicate the color “green“.「青々と茂る」(Fresh and green overgrown forest) is one of them. In English, of course, we say “fresh and green” but literally it is “blue blue” in Japanese. When the traffic lights arrived for the first time in Japan, they used to use “blue” to express the color of the green traffic light, and still they use “blue” to mean the green light in Japan.

The number of colors varies depending on languages and there are many languages that use more names to express distinctive colors and much fewer names for colors than we do. So, I would like to write about it in the next post.

*Some Japanese dialectal speakers still use “blue” to talk about things that are considered “green” in standard Japanese.


Posted by José