名 peak，summit，peak-like thing；

[例句] 即使在经验丰富的登山者中，平纳克尔峰也被认为是很难攀登的。 Even among seasoned mountaineers Pinnacle Ridge is considered quite a tough proposition.

[例句] 首次攀登珠穆朗玛峰 the first ascent of Mount Everest