Definition of maconite in US English:

maconite

noun

Mineralogy
rare
  • A hydrated aluminosilicate of potassium, magnesium, ferric iron, and aluminium.

Origin

Late 19th century. From the name of Macon County, Georgia, U.S.A. + -ite.

Pronunciation

maconite

/ˈmeɪkənʌɪt/