ベタヌ
Ainu「川の俣」
petanumedium
Batchelor explicitly gives Petanu for a fork in a river, matching 川の俣. The related historical table also supplies 川わかれ. This supports the lexical identification without settling the internal etymology.
References
Occurrences (1)
- National Institute for Japanese Language and Linguistics · 乾巻 · Page 10, line 11 · ベタヌ
…プ浜辺ピシタ浜端たシツテキシヤム ヲタシヤム川向ふベツプタ川の俣ベタヌ古川メム岡ヤ ヤタ丘陵ヤベカ川原ビタラ ツビラツカビウカ瀬ラツカ堀ヱチヤン ウヲリ シリウヲリ野…