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precipitation; deposition; settlement (e.g. of sediment)
水中の不純物が時間とともに沈澱していく。
Impurities in the water settle over time.
化学実験で沈澱物をろ過して分析した。
In the chemistry experiment, the precipitate was filtered and analyzed.
ダムの底に大量の土砂が沈澱していた。
A large amount of sediment had settled at the bottom of the dam.