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detached building; solitary house; room detached from main house
「離れ」 has another reading with different meanings.
庭の離れで客を迎えた。
I received guests in the detached building in the garden.
離れにある書斎で仕事をしている。
I work in the study in the detached building.
この旅館には庭に面した離れがいくつかある。
This inn has several detached rooms facing the garden.