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night of the full moon; the night of the 15th day of the 8th lunar month
十五夜にはお月見団子を供える習慣がある。
There is a custom of offering moon-viewing dumplings on the night of the full moon.
今年の十五夜は雲ひとつない夜空だった。
This year's full moon night had a cloudless sky.
子供の頃は十五夜を楽しみに待っていた。
As a child, I looked forward to the night of the full moon.