also: そ
noun
Abbreviation of ソビエト (Soviet), used in compounds or historical contexts to refer to the Soviet Union. Often seen in terms like 旧ソ連 (former Soviet Union).
See also: ソビエト
旧ソ連の崩壊は1991年だった。
The collapse of the former Soviet Union was in 1991.
ソ連時代の建物がまだ残っている。
Buildings from the Soviet era still remain.
Full form of the word; ソ is the abbreviated form used in compounds like ソ連 (Soviet Union).
Abbreviation of ソビエト, from Russian 'совет' (soviet).