gendarme
zhon-DARM
A rock tower or pinnacle on a mountain ridge that blocks progress along the crest, forcing climbers to detour around or over it. Gendarmes guard the ridge the way policemen guard a street — you don't pass without dealing with them.
Etymology
French gendarme, a policeman, from gens d'armes, men at arms. The rock formation blocks your passage like a policeman demanding credentials. The climbing usage originated in the French Alps.
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