[random_ind_dude]

I started reading the accepted answer on Stack Exchange, found it unconvincing and went to Wikipedia to look at the entry for axe. There I found that Yue is a type of Chinese battle axe.

The ball is probably Chinese-made. So I believe the answer that talks about Yué as the Chinese word for battle axe is the right one.

Wikipedia has an image of this rather odd-looking, but beautiful Shang dynasty Yue.

https://en.m.wikipedia.org/wiki/Battle_axe#/media/File%3ACMO...

[CRConrad]

So does the Chinese (Mandarin? Cantonese?) word for "submarine" begin with a 'U'...?

Naah, the Swedish hypothesis is far more convincing.