鉄渋かなしぶ

noun

aqueous iron rust

Technical term for rust formed in water or moisture, often seen in contexts like plumbing, metal corrosion, or traditional ironwork.

• 古ふるい水すい道どう管かんから鉄渋かなしぶが出でて、水みずが赤あかくなった。

  Aqueous iron rust came out of the old water pipe, turning the water red.