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Union of Soviet Socialist Republics

noun
  1. a former federal union of 15 constituent republics, in E Europe and W and N Asia, comprising the larger part of the former Russian Empire: dissolved in December 1991. 8,650,069 sq. mi. (22,402,200 sq. km). Capital: Moscow. Abbreviation: U.S.S.R., USSR
Also called Russia, Soviet Union.
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British Dictionary definitions for soviet union

Union of Soviet Socialist Republics

noun
  1. the official name of the former Soviet Union
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
soviet union in Culture

Union of Soviet Socialist Republics

Official name of the former Soviet Union.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.