
Subbotnik and voskresnik (from p=sʊˈbotə for Saturday and воскресе́нье, IPA for Sunday) were days of volunteer work following the October Revolution. The tradition is continued in modern Russia and some other former Soviet Republics. Subbotniks are mostly organized for cleaning the streets of garbage, fixing public amenities, collec...
Found on
http://en.wikipedia.org/wiki/Subbotnik

Working for a day in the interests of society without pay, almost always on a day off. From “subbota,” the Russian word for Sunday.
Found on
http://soviethistory.msu.edu/glossary/
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