ハーケン

noun

piton; climbing peg

Specifically a metal spike or peg driven into rock or ice for protection or aid in mountaineering.

from German Haken

• 岩がん壁ぺきにハーケンを打うち込こむ。

  Drive a piton into the rock face.

noun

hook

General hook shape or function; less common than the climbing sense. Often used in compound terms or technical contexts.

• この金かな具ぐはハーケン型がたのフックです。

  This metal fitting is a piton-type hook.