gray·​wacke ˈgrā-ˌwak How to pronounce graywacke (audio)
: a coarse usually dark gray sandstone or fine-grained conglomerate composed of firmly cemented fragments (as of quartz or feldspar)

Word History


partial translation of German Grauwacke

First Known Use

1805, in the meaning defined above

Time Traveler
The first known use of graywacke was in 1805

Dictionary Entries Near graywacke

Cite this Entry

“Graywacke.” Dictionary, Merriam-Webster, Accessed 21 Apr. 2024.

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