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head house; main family
founder (of a certain school, style, etc.); originator; birthplace
お盆に親族が本家に集まった。
The relatives gathered at the main family's house for Obon.
本家の蔵を取り壊すことになった。
It was decided to tear down the main family's storehouse.
この寺は宗派の本家として知られている。
This temple is known as the head house of the sect.