WordNet (r) 3.0 (2006):

public assistance
    n 1: governmental provision of economic assistance to persons in
         need; "she lives on welfare" [syn: social welfare,
         welfare, public assistance]

Moby Thesaurus II by Grady Ward, 1.0:

52 Moby Thesaurus words for "public assistance":
   ADC, Medicaid, Medicare, aid, alimony, allotment, allowance,
   annuity, assistance, bounty, cradle-to-grave security,
   depletion allowance, dole, fellowship, financial assistance, grant,
   grant-in-aid, guaranteed annual income, guaranteed income,
   health insurance, help, old-age assistance, old-age insurance,
   pecuniary aid, pension, price support, public welfare, relief,
   retirement benefits, scholarship, sickness insurance,
   social insurance, social security, social welfare,
   socialized medicine, state medicine, stipend, subsidization,
   subsidy, subvention, support, tax benefit,
   unemployment compensation, unemployment insurance, welfare,
   welfare aid, welfare capitalism, welfare payments, welfare state,
   welfare statism, welfarism, womb-to-tomb security