河川(かせん)

かせん
noun
river; rivers and streams
formalgeography
1. river; rivers and streams; waterways
A formal, collective term for rivers and streams. Used primarily in official, administrative, scientific, and news contexts rather than everyday conversation.
河川(かせん)の水位(すいい)が上昇(じょうしょう)している。
The river's water level is rising.
河川(かせん)敷(じき)でバーベキューをする人(ひと)が増(ふ)えている。
More people are having barbecues on the riverbank.
大雨(おおあめ)による河川(かせん)の氾濫(はんらん)を防(ふせ)ぐため、堤防(ていぼう)の整備(せいび)が急(いそ)がれている。
Improvements to embankments are being expedited to prevent river flooding due to heavy rain.

Usage

河川(かせん) is the formal/administrative term for rivers. In everyday speech, 川(かわ) (river) is used. 河川(かせん) appears in news, government documents, and technical contexts. The compound combines 河(か) (large river) and 川(せん) (river/stream), so it covers waterways of all sizes.

Common collocations

  • 河川(かせん)敷(じき): riverbed, riverside open space
  • 河川(かせん)の氾濫(はんらん): river flooding
  • 河川(かせん)管理(かんり): river management
  • 河川(かせん)工事(こうじ): river construction/maintenance work
  • 一級(いっきゅう)河川(かせん): class-1 river (managed by national government)

Related Words

Synonym: 川(かわ) (river (everyday))
Related: 河口(かこう) (mouth of a river)
Compare: 水流(すいりゅう) (water current)
Homophone: 寡占(かせん) (oligopoly)
general
Added 2026.2.24 16:33 · Revised 2026.9.2 13:01
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