Is 三角 pronounced "sangaku" in any dialects?


The word
[三角](https://ja.wikipedia.org/wiki/%E4%B8%89%E8%A7%92%E7%B5%9E%E3%82%81) is
often used in judo to describe a position enclosing your opponent's head and
arm in a "triangle" created by interlocking your legs. However this word is
occasionally spelled _san **g** aku_ (as opposed to the expected _san **k**
aku_):

> **37.** Omote-sangaku  
>  **38.** Ashi-sangaku-garami  
>  ...  
>  **45.** Yoko-sangaku
>
>   * _Fighting Judo_ , Katsuhiko Kashiwazaki
>

Is this just a typo, or an example of rendaku in the author's dialect?

i.e. is 三角 ever pronounced さん **が** く?




[Weblio's hits for
さんがく](https://www.weblio.jp/content/%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F)
don't include 三角, which would suggest that this isn't standard.

Google searches for
["よこさんがく"](https://www.google.com/search?q=%22%E3%82%88%E3%81%93%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F%22)
and
["あしさんがく"](https://www.google.com/search?q=%22%E3%81%82%E3%81%97%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F%22)
also return zero hits, while searches for
["よこさんかく"](https://www.google.com/search?q=%22%E3%82%88%E3%81%93%E3%81%95%E3%82%93%E3%81%8B%E3%81%8F%22)
and
["あしさんかく"](https://www.google.com/search?q=%22%E3%81%82%E3%81%97%E3%81%95%E3%82%93%E3%81%8B%E3%81%8F%22)
with the unvoiced か return relevant sites.

I see that [Kashiwazaki is from
Iwate](https://en.wikipedia.org/wiki/Katsuhiko_Kashiwazaki), and I believe
that this kind of softening or additional voicing is a feature of dialects in
the northeast. I lived in Morioka for a while years ago, and was interested to
hear such additional voicing among the speakers there, things like 度【たび】 being
pronounced as たんび, or a kind of interjectionary particle a bit like ね or そう,
but realized as んだ.

→ This leads me to think that the さんがく pronunciation might be an expression of
Kashiwazaki's Iwate-ben.




[Weblio's hits for
さんがく](https://www.weblio.jp/content/%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F)
don't include 三角, which would suggest that this isn't standard.

Google searches for
["よこさんがく"](https://www.google.com/search?q=%22%E3%82%88%E3%81%93%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F%22)
and
["あしさんがく"](https://www.google.com/search?q=%22%E3%81%82%E3%81%97%E3%81%95%E3%82%93%E3%81%8C%E3%81%8F%22)
also return zero hits, while searches for
["よこさんかく"](https://www.google.com/search?q=%22%E3%82%88%E3%81%93%E3%81%95%E3%82%93%E3%81%8B%E3%81%8F%22)
and
["あしさんかく"](https://www.google.com/search?q=%22%E3%81%82%E3%81%97%E3%81%95%E3%82%93%E3%81%8B%E3%81%8F%22)
with the unvoiced か return relevant sites.

I see that [Kashiwazaki is from
Iwate](https://en.wikipedia.org/wiki/Katsuhiko_Kashiwazaki), and I believe
that this kind of softening or additional voicing is a feature of dialects in
the northeast. I lived in Morioka for a while years ago, and was interested to
hear such additional voicing among the speakers there, things like 度【たび】 being
pronounced as たんび, or a kind of interjectionary particle a bit like ね or そう,
but realized as んだ.

→ This leads me to think that the さんがく pronunciation might be an expression of
Kashiwazaki's Iwate-ben.

