The kanji 瀬 primarily means "shallow part of a river," "rapid," or "shoal." It refers to a specific place in a river where the water is relatively shallow, often with a rocky or gravelly bottom, and the current is stronger. It can also figuratively describe places or situations that are turbulent or challenging.

・On-yomi (音読み): せ (se) ・Kun-yomi (訓読み): せ (se) (This is the most common reading and used when referring to the meaning of "shallow part of a river.")

⚫︎瀬戸内海 (Seto Naikai) Translation: The Seto Inland Sea (a body of water in Japan) ⚫︎急瀬 (kyuuse) Translation: rapids; fast-flowing water ⚫︎瀬 (se) Translation: shallows, rapids (used on its own, generally as a place name)

The kanji 瀬 is a phono-semantic compound (形声文字, keisei moji). The left side is the radical 水 (water, 水) indicating the meaning, and the right side is 頼 (ra/lai), which indicates the sound (phonetic component). The combination thus suggests a place related to water, in particular, a shallow or rapidly flowing part of a river, where the water's appearance is due to the presence of the rapids.