- the Kremlin,
- the executive branch of the government of Russia or of the Soviet Union, especially in regard to its foreign affairs.
- the citadel of Moscow, including within its walls the chief offices of the Russian and, formerly, of the Soviet government.
- the citadel of any Russian city
- the 12th-century citadel in Moscow, containing the former Imperial Palace, three Cathedrals, and the offices of the Russian government
- (formerly) the central government of the Soviet Union
1660s, Cremelena, from Old Russian kremlinu, later kremlin (1796), from kreml’ “citadel, fortress,” perhaps of Tartar origin. Originally the citadel of any Russian city, now especially the one in Moscow. Used metonymically for “government of the U.S.S.R.” from 1933. The modern form of the word in English might be via French.