Saw this on facebook. It has been long debated whether 南越 Nanyue, and the ethnicity generally referred to as 越 historically (prior to the Ming dynasty) spoke Austronesian, Austroasiatic, or Hmong–Mien languages.
Since Vietnam (越南) claims their name came from 南越, some people have always maintained that it was Austroasiatic speaking. However, when the name 越南 was given to Jiaozhi (交趾), then under the Nguyễn dynasty, by Emperor Jiaqing of the Qing dynasty in 1802, King Nguyễn Phúc Ánh actually requested for 南越, but Emperor Jiaqing didn’t want it to be confused with the historic 南越, and since Vietnam is located further south of the historic territory of 南越 anyway, he named it 越南 which means farther south of Nanyue.
Anyway, a clue is offered in Shuowen Jiezi Xichuan (說文解字繫傳) written by Xu Xuan (徐鉉 916-991). Under the entry of 獀, the explanation given is:
南越名犬獿獀。从犬叜聲所鳩切
People of Nanyue call a dog *ou-sou. The character 獀 has the dog radical, and sounds like 叜 (sou), has the initial of 所 (s) and the final of 鳩 (ou).
916-991 is right between Early Middle Chinese and Late Middle Chinese, so I’m going with the Taigi literary reading.
The first character is the original character for monkey 夒 with a dog radical. By Middle Chinese, 夒 already read as hou, as opposed to nu, the original pronunciation of 夒, or gau, which would have been closer to the OC /*mə-ɡˤ(r)o/ 沐猴.
So, 10th century dictionary says that dog is *hou-sou or *ou-sou in Nanyue languages. making it a cognate with PAn *asu or *u-asu for dog. Cognates: Bunun asu, Sikizaya wacu, Trobiawan watsu, Sirayan asu, Thao atu, Paiwan vatu, Tagalog aso, Tetum asu, Iban asu.
Together with the tribal name 諸稽 *ta-kˤij for the King of Yue (2500 years ago) seems to be related to the PAn word for sword *takis, it seems to point to historic Yue being Austronesian speakers.