The Meaning of gesui [下水] In Japanese

下水
げすい
Romaji: gesui N3

What does 下水 mean?

Translation and Meaning

sewage, wastewater, drainage water

Definition

下水 means sewage or wastewater; it refers to used water that carries waste and is carried away through a sewer system for treatment.

Type

noun (名詞)

Stroke Order

Meanings

  • Sewage or wastewater produced by households and industry, typically conveyed through a sewer network.
  • The sewer system or drainage network as an infrastructure concept in urban sanitation.
  • In technical discourse, relates to wastewater management and treatment processes.

Origin

Origin in historic urban Japan, with early sewer infrastructure appearing in Edo-period cities and expanding during Meiji modernization; the term gradually formalized to denote wastewater and sewerage in public and technical contexts.

Composition

  • 下 – below, down
  • 水 – water
  • Combined, 下水 denotes water that moves away from the surface, i.e., wastewater carried to a sewer or drainage system.

Usage

Used primarily in formal and technical contexts such as civil engineering, urban planning, sanitation policy, and wastewater management. In everyday speech, the term is understood and often contrasted with terms like 汚水 and 排水 depending on nuance; when specifically referring to the infrastructure, 下水道 is preferred.
💡 Tips
Mnemonic: visualize water below the ground flowing into underground pipes; the sound gesui echoes as water going down the line—remember by thinking ‘below water’ as the city’s waste water route.

Variations

  • 汚水 (osui) – wastewater
  • 排水 (haisui) – drainage, runoff
  • 排水溝 (haisuikō) – drainage channel
  • 下水道 (gesuido) – sewer system

Example Phrases

  • 下水の匂いがするので、窓を閉めた。
    gesui no nioi ga suru node, mado o shimeta.
    Because there’s a sewage smell, I closed the window.
    Lista:
    • 下水 (gesui) – sewage
    • の (no) – of
    • 匂い (nioi) – smell
    • が (ga) – [subject marker]
    • する (suru) – to do
    • ので (node) – because
    • 窓 (mado) – window
    • を (o) – [object marker]
    • 閉めた (shimeta) – closed
    「下水」 is a noun meaning sewage; in this context it combines with の匂いがする to express a smell of sewage.
下水