Why 郡 [gun] is translated as "district"? According
to the dictionary, a district is a any part of an administrative
division. This can be a region, a prefecture, a city, etc. So... it's correct to say that a 郡 is a district?
It's tricky to correctly translate words like this, because in English, different words are going to mean different things depending on what country you live in.
In US terminology, I would say that a 郡 would be more like a 'county' - they're subdivisions of Prefectures that are then divided into towns or villages. For example, my address in Japan was 宮城県加美郡加美町宮崎字 - Miyagi Prefecture, Kami-gun (county/district), Kami-machi (town), Miyazaki-aza (Kami town is made of three former towns that merged together about ten years ago - Miyazaki, Onoda, and Nakaniida. The three former towns are still recognized as separate sections of the current town.)
Unless you live in a city, all addresses are going to be broken down in the same way:県 (or 道/府, depending on where you are),郡、町(or 村). If you live in a city, the address will be 県、市、区 (区, readく, is most commonly translated as a "ward")
Yeah, I have read that 郡 are more like American counties, but well... I'm from Argentina and here we don't have counties either. So, I was looking for the real meaning of "county" and I found the same problem again. The meaning of "county" in USA is different to other countries. A county is a territory governed by a count and counts are chosen by monarchs.
So, in the end I concluded that American counts are subdivisions of the states and Japanese districts are subdivisions of prefectures. And I guess they just exist for better administration. Thus I would like to say Japanese districts are "sub-prefectures", but actually Japanese prefectures have a subdivision called "sub-prefectures".
So, the real question now is... what's the difference between a subprefecture and a district?
Ok, I had never heard of the term "sub-prefecture" before, so I looked it up. Here is the Wikipedia article I found: https://en.wikipedia.org/wiki/Subprefectures_of_Ja... (the Spanish version was decidedly less informative, so I'm linking the English). Apparently, "sub-prefectures" only exist now in a few prefectures, which are really just branches of the Prefectural Offices located in areas of the Prefecture that would be hard to reach otherwise (for example, a few islands far from the rest of the prefecture, or a remote mountainous area) by the prefectural offices. These 'sub-prefectures' work just as representation of the prefectural government, not as their own government, and they don't really seem to do much.
