Definition of biotite in English:


Line breaks: bio|tite
Pronunciation: /ˈbʌɪətʌɪt


[mass noun]
  • A black, dark brown, or greenish black micaceous mineral, occurring as a constituent of many igneous and metamorphic rocks.
    More example sentences
    • Although dark minerals such as biotite and hornblende are usually present, giving the rock a speckled appearance, they are never abundant.
    • Quartz, feldspar, white mica and biotite are all major constituents.
    • All four samples are medium-grained, and comprise variable proportions of hornblende, feldspar and quartz with accessory biotite and titanite.


mid 19th century: named after J.-B. Biot (1774–1862), French mineralogist.

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Pronunciation: ˈmeɪlstrəm
a powerful whirlpool in the sea

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