| Union of Soviet Socialist Republics. |
| Union of Soviet Socialist Republics Commonly called Soviet Union or Russia Abbr. USSR A former country of eastern Europe and northern Asia with coastlines on the Baltic and Black seas and the Arctic and Pacific oceans. It was established in December 1922 with the union of the Russian SFSR (proclaimed after the Russian Revolution of 1917) and various other soviet republics, including Belorussia and the Ukraine. In 1991 a number of consituent republics declared their independence, and the USSR was officially dissolved on December 31, 1991. Moscow was the capital. |
| USSR abbr. Union of Soviet Socialist Republics |
Abbreviation for Union of Soviet Socialist Republics, the official name of the former Soviet Union.
| USSR Union of Soviet Socialist Republics |