chockstone

British  

/ ˈtʃɒkˌstəʊn /

noun

1. a stone securely jammed in a crack. It may vary in size from a pebble to a large boulder

2. another name for chock

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Example Sentences

A climbing party just below him was sitting atop a refrigerator-sized block—called a chockstone—when the block moved, dropping a few feet down into a wide crack in the back of the ledge.

From National Geographic

Chockstone wedging is “a recognized way of levering large flakes off of cliffs,” Stock says, though he can’t say for sure whether the incident Haas described ultimately led to the July 3rd rockfall.

From National Geographic

Chockstone: a northern word for a stone wedged between the sides of a gully.

From Project Gutenberg

I have to contort my body to get under a human-sized chockstone trapped in mid-air and begin to understand, in the vaguest way, how Aron Ralston might have felt.

From The Guardian

With immense labour I found a chockstone above my head, and managed to force my foot free.

From Project Gutenberg