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

Example Sentences

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 example sentences are selected automatically from various online news sources to reflect current usage of the word 'arkose.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History



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 27 Mar. 2023.

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