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tatami room; tatami mat room; formal Japanese room
dinner party in a tatami room (esp. when a geisha or maiko attends)
坐敷の障子を開けて庭を眺めた。
I slid open the shoji in the tatami room and gazed at the garden.
坐敷に布団を敷いて泊まった客もいた。
Some guests stayed over with futon laid out in the tatami room.
この旅館の坐敷は十二畳もある。
The tatami room in this inn is a whole twelve mats.