Definition of pennantite in English:

pennantite

noun

Mineralogy
  • A mineral of the monoclinic crystal system which consists of a hydroxide and aluminosilicate of manganese, and occurs as minute orange-red pleochroic flakes.

Origin

1940s. From the name of Thomas Pennant, Welsh zoologist and mineralogist + -ite.

Pronunciation

pennantite

/ˈpɛnəntʌɪt/