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Commonwealth of Independent States

noun
  1. an alliance of former Soviet republics formed in December 1991, including: Armenia, Azerbaijan, Belarus, Kazakhstan, Kyrgyzstan, Moldova, Russian Federation, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan. Abbreviation: C.I.S.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for commonwealth of independent states

Commonwealth of Independent States

noun
  1. a loose organization of former Soviet republics, excluding the Baltic States, formed in 1991Abbreviation: CIS
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