rockfall

[ rok-fawl ]
/ ˈrɒkˌfɔl /
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noun

an act or instance of the falling of rock, as in a cave-in or an avalanche.
a mass of rocks that have fallen: to be trapped under a rockfall.

Origin of rockfall

First recorded in 1920–25; rock1 + fall
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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