WordNet (r) 3.0 (2006):

price support
    n 1: a government subsidy used to maintain prices at a certain
         level

Moby Thesaurus II by Grady Ward, 1.0:

90 Moby Thesaurus words for "price support":
   TLC, aid, alimony, allotment, allowance, annuity, assistance,
   autarky, bimetallism, bounty, bread, care, daily bread,
   depletion allowance, dole, economic self-sufficiency,
   economic support, endowment, fair trade, fair-trade agreement,
   fair-trading, fellowship, financial assistance, flexible supports,
   free enterprise, free trade, governmentalism, grant, grant-in-aid,
   guaranteed annual income, help, keep, laissez-faire,
   laissez-faireism, line, livelihood, living, localism, maintenance,
   managed currency, managed prices, manna, meat, mothering,
   noninterference, nonintervention, nourishment, nullification,
   nurture, old-age insurance, party line, party principle,
   pecuniary aid, pension, planned economy, policy, polity, position,
   price controls, price supports, price-fixing, protection,
   protectionism, provision, public assistance, public policy,
   public welfare, pump-priming, relief, rent control,
   retirement benefits, rigid supports, scholarship, sectionalism,
   stipend, subsidization, subsidy, subsistence, subvention, support,
   sustainment, sustenance, sustentation, tax benefit,
   tender loving care, upkeep, valorization, welfare, welfare aid,
   welfare payments