muscovite

noun1

1. •
   A pale brown mineral of the mica group, being a basic potassium aluminosilicate with the chemical formula KAl₂(Si₃Al)O₁₀(OH,F)₂; used as an electrical insulator etc.

adjective2

1. •
   Of or relating to Muscovy or Moscow, or the people of these places.
2. •
   Russian.

noun2

1. •
   An inhabitant or native of Muscovy or Moscow.
2. •
   (no longer used) A Russian.