源げん流りゅう

noun

source of a river; headwaters

Refers to the geographical origin point or upper reaches of a river or stream.

• その川かわの源げん流りゅうは深ふかい山やまの中なかにある。

  The source of that river is deep in the mountains.

noun

origin; source

Metaphorical extension: the starting point or root of something continuous like a tradition, culture, language, or thought.