ar·​kose ˈär-ˌkōs How to pronounce arkose (audio)
: a sandstone characterized by feldspar fragments that is derived from granite or gneiss which has disintegrated rapidly
arkosic adjective

Examples of arkose in a Sentence

Recent Examples on the Web Its heavy concentration of feldspar grains — known as arkose — means the rock is inevitably prone to chemical decay. Washington Post, 2 Apr. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'arkose.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from French, of obscure origin

Note: The word was introduced by the French geologist Alexandre Brongniart (1770-1847), probably first in the article "Macigno" in the Dictionnaire des sciences naturelles, tome 27 (Strasbourg/Paris, 1823), p. 498. Brongniart says nothing about its etymology.

First Known Use

1829, in the meaning defined above

Time Traveler
The first known use of arkose was in 1829

Dictionary Entries Near arkose

Cite this Entry

“Arkose.” Dictionary, Merriam-Webster, Accessed 13 Jun. 2024.

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