Source : Webster's Revised Unabridged Dictionary (1913)

Kremlin \Krem"lin\, n. [Russ. kremle.]
   The citadel of a town or city; especially, the citadel of
   Moscow, a large inclosure which contains imperial palaces,
   cathedrals, churches, an arsenal, etc. [Russia]

Source : WordNet®

Kremlin
     n 1: citadel of Moscow, housing the offices of the Russian
          government
     2: citadel of a Russian town