social security - public provision for the economic, and sometimes social, welfare of aged, unemployed, etc., esp. through pensions and other monetary assistance; a government programme designed to provide such assistance, social insurance - government insurance providing coverage for the unemployed, the injured, the old, etc: usually financeb by contributions from employers and employees, as well as general government revenue, organisation privée fonctionnant sous le controle de l'Etat, destinée a garantir les travailleurs et leurs familles contre les risques de toute nature susceptibles de réduire leur capacité de gain, a couvrir les charges de maternité et les charges de familles qu'ils supportent