Where does “Ca-bun” come from?

Ca-bun (Vietnamese) comes from English Kabul, from Classical Persian کَابُل.

Ancestry of “Ca-bun”, step by step

Ca-bun traces back through two separate lines of ancestry.

via English Kabul

StepLanguageWordMeaning
1EnglishKabul
2Classical Persianکَابُل

via Russian Кабу́л

StepLanguageWordMeaning
1RussianКабу́л
Every word from Classical Persian کَابُلEvery word from English Kabul