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floor
stage (for the narrator and the shamisen player)
dining platform built across a river
「床」 has other readings with different meanings.
床に座って話を聞いていたよ。
I was sitting on the floor listening.
文楽の上演では、太夫と三味線弾きが床に並び、人形遣いの動きに合わせて語りと演奏を進めていく。
In a bunraku performance, the chanter and shamisen player line up on the chanter's stage and proceed with their narration and accompaniment in time with the puppeteers' movements.
この床はとても滑りやすいんだ。
This floor is very slippery.