Added 9 October 2026 ussr noun Categories: PlacesUncommon Words noun ! Definition from WordNet 3.1, Princeton University. More about ussr at Wordnik → Where our words come from → A former communist country in eastern Europe and northern Asia; established in 1922; included Russia and 14 other soviet socialist republics (Ukraine and Byelorussia and others); officially dissolved 31 December 1991. Related Words: russiasovietfederationfsurepublicscccpsovietskremlinredstateunion Back to today's word