social security: social welfare program in the U.S.; includes old-age and survivors insurance and some unemployment insurance and old-age assistance
social insurance: government provision for unemployed, injured, or aged people; financed by contributions from employers and employees as well as by government revenue
marxism: the economic and political theories of Karl Marx and Friedrich Engels that hold that human actions and institutions are economically determined and that class struggle is needed to create historical change and that capitalism will ultimately be superseded by communism