坊ぼう主ず畳だたみ

noun

tatami mat without a decorative cloth edge

Refers to a tatami mat that lacks the usual 'heri' (縁) border; often associated with a simple, rustic, or Zen aesthetic.

See also: へり

• この茶ちゃ室しつには坊ぼう主ず畳だたみが敷しいてある。

  This tea room is laid with tatami mats without decorative edges.