1.A member of the extreme left wing of the Social Democratic Party that seized power in Russia in 1917 after the Russian October Revolution, and advocated rule by the proletariat and state ownership of property. Note: Actually in the minority, this branch seized the opportunity, when the moderate group walked out, to proclaim themselves a majority and form a government. They prevailed in the subsequent civil war.
2.Same as communist, especially used of Russian communists.
3.Anyone with communist leanings or sympathies; used very loosely in a derogatory sense by some people with economically conservative views.
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