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mountain (or hill) behind a house, village, etc.
side of a mountain that gets little sunshine
envious; jealous; jelly
子供たちが裏山へ駆け上がった。
The children ran up the mountain behind the house.
大雨で裏山に土砂崩れ警報が出された。
A landslide warning was issued for the mountain behind the house due to heavy rain.
裏山には、珍しい山野草がたくさん自生している。
Many rare wild plants grow naturally on the mountain behind the house.