anorthosite

[ an-awr-thuh-sahyt ]

noun

, Petrology.

1. a granular plutonic rock composed largely of labradorite or a more calcic feldspar.

anorthosite

/ ænˈɔːθəˌsaɪt /

noun

1. a coarse-grained plutonic igneous rock consisting almost entirely of plagioclase feldspar

anorthosite

/ ăn-ôr′thə-sīt′ /

1. An igneous rock consisting almost entirely of plagioclase feldspar, especially the labradorite variety. Anorthosites have been identified among rock samples collected from the Moon.

Other Words From

• an·or·tho·sit·ic [an-aw-th, uh, -, sit, -ik], adjective

Word History and Origins

Origin of anorthosite¹

1860–65; < French anorthose anorthoclase ( an- an- ¹ + Greek orthós straight) + -ite ¹

Word History and Origins

Origin of anorthosite¹

C19: from French anorthose (see an- , ortho- ) + -ite ¹

Example Sentences

In Canada great portions of the eastern portion of the Dominion are formed of gabbros, norite, anorthosite and allied rock types.

From Project Gutenberg