肌はだ落おち

noun

loose rockfall

Mountaineering term for loose rocks that fall or are easily dislodged, often used in warnings about unstable terrain.

• このルートは肌はだ落おちが多おおいのでヘルメットを着ちゃく用ようしてください。

  This route has a lot of loose rockfall, so please wear a helmet.