How was the Pacific Ocean named in Japan before Magellan?


The word 太平洋｛たいへいよう} can be translated literally as "peaceful ocean" as
somebody noticed in the question [Oceans ー Thick or
Big?](https://japanese.stackexchange.com/q/13219/14283).

But, as far as I know, the name was invented by Ferdinand Magellan:
<https://oceanservice.noaa.gov/facts/pacific.html>.

My question is, how was this area of water named by Japanese people before
getting in contact with Europeans?




[This](https://okwave.jp/qa/q8821250.html) is a great answer, I think. To
summarize in English, in the olden days, people didn't really need to refer to
separate oceans in the same sense we do today, and would instead denote narrow
regions of ocean by the areas of land they were closest to, or by adding
[灘]{なだ} onto the end to denote a tough-to-sail area of ocean. Even 瀬戸内 didn't
get its name until the end of the 江戸 era, before which it was named in
sections like how I described above.




[This](https://okwave.jp/qa/q8821250.html) is a great answer, I think. To
summarize in English, in the olden days, people didn't really need to refer to
separate oceans in the same sense we do today, and would instead denote narrow
regions of ocean by the areas of land they were closest to, or by adding
[灘]{なだ} onto the end to denote a tough-to-sail area of ocean. Even 瀬戸内 didn't
get its name until the end of the 江戸 era, before which it was named in
sections like how I described above.

