Are the Japanese and Korean spoken languages somehow related?


According to Wikipedia,

> Historical and modern linguists classify Korean as a language isolate. [A
> language isolate, in the absolute sense, is a natural language with no
> demonstrable genealogical ... relationship with other languages]

Yet whenever I hear Korean spoken, my ear is tricked for a short time into
turning on "Japanese mode"; there are resemblances to Japanese in vocal
cadence, pitch variation, syllable enunciation, morae timing, etc. Then I
start wondering why I'm not understanding a single word, until I realize I'm
not hearing Japanese at all.

The first time this happened to me I was at a hotel in Los Angeles and was
flipping through channels on the TV. I was much newer to Japanese at that
point and thought I simply didn't have enough practice to understand any rapid
speech at all. I watched for about a minute, puzzled, until the screen showed
an American speaking English together with some subtitles in Hangul, and I
realized this was a Korean show.

Are the two languages actually related in some unrecognized way? Or am I
perhaps the only one whose brain initially tries to run Korean through a
Japanese filter?




I'm a native Japanese speaker, and I have experienced this, too. Depending on
the weather condition, it's possible to listen to Korean AM radio in Japan.
When the noise is _very_ strong, I sometimes find it difficult to distinguish
whether it's in Japanese or in Korean.

I guess this is mainly because of the intonation rather than actual
vocabulary. I feel the two languages have similar rhythms when spoken, and
they are both relatively "flat" in terms of intonation. (This is my personal
experience, and I have no idea if it's academically correct or if it's a
coincidence.) On the other hand, the 'four tones' in Chinese sound very
distinct to my ears.

In addition, the two languages do share many words of the same Chinese or
English roots, and the pronunciations of such words are similar. For example,
compare the pronunciation of
[大学生](https://ja.forvo.com/word/%E5%A4%A7%E5%AD%A6%E7%94%9F/) and
[대학생](https://ja.forvo.com/word/%EB%8C%80%ED%95%99%EC%83%9D/) ("university
student"). On the other hand, native vocabularies are completely different (eg
[猫](https://ja.forvo.com/word/%E7%8C%AB/#ja) vs
[고양이](https://ja.forvo.com/word/%EA%B3%A0%EC%96%91%EC%9D%B4/#ko) for "cat"),
and I think this is why they are unrelated in the linguistic sense.

**EDIT:** Both languages are surprisingly similar in terms of grammar, too.
Machine translation works much better between Japanese and Korean than between
Japanese and Chinese/English/etc. I don't know why, and apparently linguists
don't know much about the reason, either. I found this Wikipedia article:
[Comparison of Japanese and
Korean](https://en.wikipedia.org/wiki/Comparison_of_Japanese_and_Korean#Grammar)




I'm a native Japanese speaker, and I have experienced this, too. Depending on
the weather condition, it's possible to listen to Korean AM radio in Japan.
When the noise is _very_ strong, I sometimes find it difficult to distinguish
whether it's in Japanese or in Korean.

I guess this is mainly because of the intonation rather than actual
vocabulary. I feel the two languages have similar rhythms when spoken, and
they are both relatively "flat" in terms of intonation. (This is my personal
experience, and I have no idea if it's academically correct or if it's a
coincidence.) On the other hand, the 'four tones' in Chinese sound very
distinct to my ears.

In addition, the two languages do share many words of the same Chinese or
English roots, and the pronunciations of such words are similar. For example,
compare the pronunciation of
[大学生](https://ja.forvo.com/word/%E5%A4%A7%E5%AD%A6%E7%94%9F/) and
[대학생](https://ja.forvo.com/word/%EB%8C%80%ED%95%99%EC%83%9D/) ("university
student"). On the other hand, native vocabularies are completely different (eg
[猫](https://ja.forvo.com/word/%E7%8C%AB/#ja) vs
[고양이](https://ja.forvo.com/word/%EA%B3%A0%EC%96%91%EC%9D%B4/#ko) for "cat"),
and I think this is why they are unrelated in the linguistic sense.

**EDIT:** Both languages are surprisingly similar in terms of grammar, too.
Machine translation works much better between Japanese and Korean than between
Japanese and Chinese/English/etc. I don't know why, and apparently linguists
don't know much about the reason, either. I found this Wikipedia article:
[Comparison of Japanese and
Korean](https://en.wikipedia.org/wiki/Comparison_of_Japanese_and_Korean#Grammar)

