[NovemberWhiskey]

The "go" signal in traffic lights in Japan is 青い (あおい) "aoi".

That adjective in Japanese means both blue and green. The Japanese language didn't have a widely-adopted word for just "green" - 緑 (みどり) "midori" - until after WWII.

Green apples or vegetables are still "aoi", for example. I lived in Japan for four years and never saw a blue traffic light.

[fenomas]

This is pretty far off base - for a start, the first JP law on traffic lights in the 1930s used midori, not ao. Per jp references, ao/midori split into distinct meanings around the Heian~Kamakura periods (so 800-1000 years ago).

[SECProto]

> for a start, the first JP law on traffic lights in the 1930s used midori, not ao.

Have a source for that? This section[1] of the ja.wikipedia article could apparently use your revisions - both kanji are acceptable.

[1] https://ja.wikipedia.org/wiki/%E4%BA%A4%E9%80%9A%E4%BF%A1%E5...

[fenomas]

I don't follow. Are you suggesting the link you posted contradicts something I said?

If you want a source that the 1930 law used midori, see here, under 発祥期:

https://ja.m.wikipedia.org/wiki/%E6%97%A5%E6%9C%AC%E3%81%AE%...

[SECProto]

Are you referring to reference number 184? I'm looking for a primary source for your statement that midori was the colour standardized in law since the 1930s, because the section I linked about colours explicitly calls out ao and notes the difference in different jurisdictions.

[fenomas]

> your statement that midori was the colour standardized in law since the 1930s

In 1930, not since the 1930s. The 1930 law used midori, but it was changed to ao in 1947 after that became the more popular usage. The page you linked was about the current law.

[eric-hu]

Do you know more about the history of this color use? It’s surprising to me that midori uses the kanji for green in Chinese if it’s such a recent idea in Japan.

[Umofomia]

Green (綠) in Chinese also came later. In Old Chinese, 青 was generally used to represent both blue and green colors.

While the word 綠 to mean green has been attested as far back as 1000 BC, the idea that it was a separate color rather than describing a shade of 青 is relatively more recent. Wikipedia[0] indicates that it was adopted in the early 20th century in Chinese (as part of vernacular language reforms) and after WWII in Japanese, though these claims are currently marked with [citation needed]. While both are relatively recent, the usage in Chinese did have a longer period of time to take hold.

[0] https://en.wikipedia.org/wiki/Blue%E2%80%93green_distinction...

[my12parsecs]

I don’t know about the green kanji, but the traditional “Jueju” Poem by Chinese poet Du Fu has the line “山青花欲然”, and “青” the Kanji for Blue in Japan means green in this context, as it describes “山” which means mountain.

By the way there’s a variety of kanji that reads “aoi” in modern Japanese. 青い, 蒼い, 碧い are all “aoi”, but we use 青い mainly as blue today.

[eric-hu]

Oh that’s interesting. Yeah 青 is used in Chinese as another word for green. I don’t know that it has any connotations of blue, but I did grow up in the US, so perhaps there’s nuance to that character I’m unaware of, or the character slightly changed meaning when made a kanji.

[NovemberWhiskey]

What I was told, when I asked about this, was that "midori" existed as a Japanese word but was not in common usage. That is what Mizutani-san from JAL Academy told me back in 2009 anyway.

EDIT: I apologize for the vague sourcing!