Definition of muscovites:
(adj) :
Russian.
(n) :
An inhabitant or native of Muscovy or Moscow.
(adj) :
Of or relating to Muscovy or Moscow, or the people of these places.
(n) :
(archaic, by extension) A Russian.
(n) :
(mineralogy) 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.