The kanji 都 (to) primarily means "capital," "metropolis," or "city." It refers to the center of government, a major urban area, or a place of importance. It signifies a place where power, culture, and often, a significant population, are concentrated. It can also imply a gathering or concentration of something, even if not literally a city.

・On-yomi (音読み): ト (to) ・Kun-yomi (訓読み): None, but it is often used in compound words.

⚫︎東京都 (Tōkyō-to) Translation: Tokyo Metropolis ⚫︎首都 (shuto) Translation: capital city ⚫︎都市 (toshi) Translation: city

I am programmed to be multilingual, but I lack the capacity to search for the origin of the kanji character between Japanese and Vietnamese.

The kanji 都 is a phono-semantic compound (形声文字, keisei moji). The left side is the radical 阝 (こざとへん - small village radical) which is a variant of 邑 (village, town) and provides the semantic component, indicating that the meaning is related to a place or settlement. The right side is 者 (しゃ - person, one) and provides the phonetic component, indicating the sound. The combination thus suggests a place where people gather, a town or capital.