rock dust

  1. a crushed limestone sprayed on surfaces in mines to make coal dust incombustible in case of a gas explosion.

Origin of rock dust

First recorded in 1930–35

Words Nearby rock dust Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use rock dust in a sentence

  • Then, once in a great while, a third kind will descendthe accumulated snow and ice and rock dust of maybe half a century or more.

    Boy Scouts in Glacier Park | Walter Prichard Eaton