分ぶん水すい山さん脈みゃく

noun

watershed; divide

A mountain range that forms a drainage divide, separating river systems. Used in geography and earth science contexts.

• この分ぶん水すい山さん脈みゃくを境さかいに、川かわの流ながれが太たい平へい洋よう側がわと日本にほん海かい側がわに分わかれる。

  This watershed mountain range divides the river flow into the Pacific side and the Sea of Japan side.