Where does “Кавагути” come from?

Кавагути (Russian) comes from Japanese 川口, from Japanese 口, from Japanese くち, from Japanese 朽ちる.

Ancestry of “Кавагути”, step by step

StepLanguageWordMeaning
1Japanese川口mouth of river, estuary
2Japanese口mouth; opening; the mouth
3Japaneseくちmouth
4Japanese朽ちる—
Every word from Japanese 朽ちる →Every word from Japanese くち →Every word from Japanese 口 →