I was doing some searching and it seemed from what I found that 背広 is actually 当て字 for “Savile Row”, a famous street in London known for tailoring. Curious I checked the wanikani page and they don’t mention it, which is fine but they also list for the reading the 広 part is rendaku’d, which in actuality seems like it could be wrong. Assuming it actually is a loan word, wouldn’t it be incorrect to call it rendaku if it’s just the way it is pronounced, like there was never a shift in pronunciation, right?
Now obviously this doesn’t actually matter that much but I just thought it was interesting that such a Japanese sounding word was actually a loan word. Its possible that I’m wrong on my part also but from my basic Japanese googling it seems to be correct.
Also any other interesting examples like this? Somewhat common kanji words that are surprisingly loan words?
This is one of those words where there are multiple possible etymologies; everybody loves to leap on the “Savile Road” one and it does have some backing from serious sources, but there are other options, e.g. 日本国語大辞典 lists:
from the fact the back is made from one wide piece of cloth with no seams
the Savile Road theory
a translation of English “sack coat”
ateji of English “civil clothes” 市民服
from “cheviot” the suit material
and it suggests the “civil clothes” origin is most plausible.
日本大百科全書 lists a similar set of competing theories, and it plumps for the “wide piece of cloth” plus “wider and looser on the back than the preceding frock coats”. (I have a suspicion some of this idea must be in play even for the loanword origins; otherwise why pick these particular kanji?)
Regarding rendaku on 広, I think it’s reasonable to call it that, because although this is a kanji picked for its reading, it’s been picked for its rendakued reading. Otherwise it would be せひろ
