UdSSR in English: USSR (initialism of Union of Soviet Socialist Republics, official name of Soviet Union: a former transcontinental country in Europe and Asia (1922–1991), now split into Russia and 14 other countries; in full, Union der Sozialistischen Sowjetrepubliken)

Meanings

historicalUSSR (initialism of Union of Soviet Socialist Republics, official name of Soviet Union: a former transcontinental country in Europe and Asia (1922–1991), now split into Russia and 14 other countries; in full, Union der Sozialistischen Sowjetrepubliken)
Die UdSSR wurde im Dezember 1991 aufgelöst.