anorthosite: meaning, definition, pronunciation and examples
C2Technical/Scientific
Quick answer
What does “anorthosite” mean?
A coarse-grained igneous rock composed almost entirely of plagioclase feldspar.
Audio
Pronunciation
Definition
Meaning and Definition
A coarse-grained igneous rock composed almost entirely of plagioclase feldspar.
A type of intrusive igneous rock characterized by a high proportion (typically over 90%) of calcium-rich plagioclase feldspar, often with minor amounts of pyroxene, olivine, or iron oxides. It is significant in lunar geology and Precambrian continental crust formation.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Spelling and pronunciation follow standard regional patterns.
Connotations
None beyond its scientific definition.
Frequency
Extremely low frequency in general language. Usage is identical and confined to specialist contexts in both regions.
Grammar
How to Use “anorthosite” in a Sentence
The [geological unit] consists of anorthosite.Anorthosite is found in [location/context].Vocabulary
Collocations
Examples
Examples of “anorthosite” in a Sentence
adjective
British English
- The anorthositic layer was clearly visible.
- They identified anorthositic material in the sample.
American English
- An anorthositic composition suggests a specific magmatic history.
- The anorthositic rocks were mapped across the region.
Usage
Meaning in Context
Business
Unused in standard business contexts. May appear in reports for mining or geological surveying companies.
Academic
Common in geology, earth science, and planetary science papers, textbooks, and lectures.
Everyday
Virtually never used in everyday conversation.
Technical
The primary domain of use. Precise term in petrological classification, geological mapping, and lunar science.
Vocabulary
Synonyms of “anorthosite”
Neutral
Weak
Vocabulary
Antonyms of “anorthosite”
Watch out
Common Mistakes When Using “anorthosite”
- Mispronouncing as 'an-OR-tho-site' (stress on OR). Correct stress is on the second syllable: an-OR-tho-site.
- Using it as a general term for any light-coloured rock.
- Misspelling as 'anorthocite' or 'anorthisite'.
FAQ
Frequently Asked Questions
Anorthosite is an intrusive igneous rock made almost entirely of plagioclase feldspar.
It is found in ancient Precambrian shield areas on Earth and makes up much of the lunar highlands.
Its abundance on the Moon supports the theory that the early Moon had a molten magma ocean where dense minerals sank and light plagioclase floated to form the crust.
Yes, some varieties are mined as a source of aluminium or for use as dimension stone (like 'blue granite' countertops).
A coarse-grained igneous rock composed almost entirely of plagioclase feldspar.
Anorthosite is usually technical/scientific in register.
Anorthosite: in British English it is pronounced /ænˈɔːθəsaɪt/, and in American English it is pronounced /ænˈɔrθəˌsaɪt/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
AN ORTHOdontist might examine a rock? No — but AN + ORTHO (meaning 'straight' or 'correct' in Greek, hinting at the ordered crystal structure) + SITE (a place/rock).
Practice
Quiz
Anorthosite is primarily composed of which mineral?