orthoclase

noun

or·​tho·​clase ˈȯr-thə-ˌklās How to pronounce orthoclase (audio)
-ˌklāz
: a monoclinic mineral of the feldspar group consisting of a silicate of potassium and aluminum

Word History

Etymology

German Orthoklas, from orth- + Greek klasis breaking, from klan to break — more at clast

First Known Use

1849, in the meaning defined above

Time Traveler
The first known use of orthoclase was in 1849

Dictionary Entries Near orthoclase

orthochromatic

orthoclase

orthoclastic

See More Nearby Entries 

Cite this Entry

“Orthoclase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/orthoclase. Accessed 20 Apr. 2024.

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Kids Definition

orthoclase

noun
or·​tho·​clase ˈȯr-thə-ˌklās How to pronounce orthoclase (audio)
-ˌklāz
: a mineral consisting especially of potassium feldspar

More from Merriam-Webster on orthoclase

Britannica.com: Encyclopedia article about orthoclase

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