Definition of naumannite in US English:

naumannite

noun

Mineralogy
  • Native silver selenide, Ag₂Se, crystallizing in the orthorhombic system and usually occurring as black metallic cubes.

Origin

Mid 19th century; earliest use found in James Nicol (1810–1879), geologist. From German Naumannit from the name of Karl F. Naumann, German mineralogist + -it -ite.