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rain water
"rain water" solar term (approx. February 19)
古い屋根には雨水が溜まりやすい。
Rainwater easily collects on old roofs.
庭の水やりに雨水を利用する。
I use rainwater for watering the garden.
大雨の後は雨水が川に大量に流れ込んだ。
After the heavy rain, a large amount of rainwater flowed into the river.