洪水|こうずいkouzui[0]heiban (flat)

1. nounflood; flooding
   洪水こうずいがその村むらを飲み込のみこんでしまった。↗

   The flood overwhelmed the village.

• Synonym出水しゅっすいWrittenWritten/formal prose. A river rising and flooding; often used in disaster-prevention reports rather than everyday speech.
• Synonym大水おおみずNeutralA native Japanese word, somewhat colloquial, for a flood; e.g. 「大水が出る」.
• Synonym氾濫はんらんWrittenWritten/formal prose. Overflowing of rivers, or an oversupply of something undesirable; also used figuratively, as in 「情報の氾濫」.
• Related越流えつりゅうFormalFormal term for water spilling over a levee or the rim of a container; used mainly in river engineering.
• Antonym渇水かっすいNeutralA water shortage caused by scarce rainfall; the opposite of 「洪水」, as in 「渇水対策」.
• Antonym旱魃かんばつWrittenWritten/formal prose. A prolonged drought with no rain; the opposite of 「洪水」.

Use 「洪水」 for a river flooding disaster, as in 「洪水警報」, and figuratively for things pouring in. Say 「大水」 in casual speech, 「氾濫」 for rivers overflowing or oversupply, 「出水」 in written disaster reports, 「越流」 in engineering; the opposites are 「干ばつ」 and 「渇水」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 大雨おおあめや融雪ゆうせつによって、河川かせんの水みずが増ふえて溢れ出あふれだすこと。
2. 物ものや人ひとが大量たいりょうに押し寄おしよせること。