choss
rhymes with "boss"
Loose, rotten, crumbling, or otherwise terrible rock. A "choss pile" is an entire cliff made of the stuff. To climb on choss is to negotiate a continuous betrayal of trust between your hands and the mountain.
Etymology
British climbing slang, origin uncertain. Possibly related to dialectal English for rubbish or debris. In wide use by the mid-20th century.
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