Definition of biotite
: a generally black or dark green form of mica that is a constituent of crystalline rocks and consists of a silicate of iron, magnesium, potassium, and aluminum
biotiticplay \ˌbī-ə-ˈti-tik\ adjective
Origin and Etymology of biotite
German Biotit, from Jean B. Biot †1862 French mathematician
First Known Use: 1848
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