anorthosite

noun

an·​or·​tho·​site ə-ˈnȯr-thə-ˌsīt How to pronounce anorthosite (audio)
: a granular plutonic igneous rock composed almost exclusively of a soda-lime feldspar (such as labradorite)
anorthositic adjective

Keep scrolling for more

Example Sentences

Recent Examples on the Web The light-colored highlands are composed of anorthosite, an igneous rock believed to be the remains of the primordial crust of the Moon, and are dated to 4.5 to 3.9 billion years. David Bressan, Forbes, 10 Oct. 2021 At the moment, only two mines in Greenland are active, one producing rubies and the other anorthosite, used in paints, plastic coatings and special varieties of glass. New York Times, 1 Oct. 2021 Astronauts on Apollo 15 collected a 4 x 2-inch chunk of crystal anorthosite over 4 billion years old. Michael O’donnell, WSJ, 2 July 2021 The chunks of anorthosite weren’t deposited there by nature — they were trucked in from the mountains around Pasadena. Los Angeles Times, 19 July 2019 The chunks of anorthosite weren’t deposited there by nature — they were trucked in from the mountains around Pasadena. Los Angeles Times, 19 July 2019

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

Keep scrolling for more

Word History

Etymology

French anorthose, a feldspar, from a- + Greek orthos — more at orth-

First Known Use

1863, in the meaning defined above

Time Traveler
The first known use of anorthosite was in 1863

Dictionary Entries Near anorthosite

Cite this Entry

“Anorthosite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/anorthosite. Accessed 5 Oct. 2022.

Keep scrolling for more

More from Merriam-Webster on anorthosite

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!


Commonly Confused Words Quiz

  • vector image of a face with thought expression
  • I went to the ______ store to buy a birthday card.
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Universal Daily Crossword

A daily challenge for crossword fanatics.

TAKE THE QUIZ