rock flour
noun
Origin of rock flour
First recorded in 1880–85
Words nearby rock flour
rock dust,
rock elm,
rock falls,
rock fence,
rock fever,
rock flour,
rock flower,
rock garden,
rock glacier,
rock gunnel,
rock hill
Example sentences from the Web for rock flour
Mountains were moved piecemeal, and ground to boulders, pebbles, and rock-flour in the moving.
The Spell of the Rockies |Enos A. MillsNearly all of the soil in the Park is rock-flour that was ground by glaciers, and in part distributed by them.
Your National Parks |Enos A. MillsMountains are moved piecemeal, and are ground to boulders, pebbles, and rock-flour in the moving.
Your National Parks |Enos A. Mills
British Dictionary definitions for rock flour
rock flour
noun
very finely powdered rock, produced when rocks are ground together (as along the faces of a moving fault or during the motion of glaciers) and are thus chemically unweathered