They are entitlements.
"An “entitlement,” as a type of federal spending, is a government program in which recipients automatically receive benefits that they’re eligible for based on the applicable legislation. Social Security is an entitlement because everyone who meets the eligibility criteria (40 “quarters” of eligible earnings) is entitled to a benefit. No one is dependent on Congress to appropriate spending every year in order to receive their Social Security checks."
By the plain definition of the term, Social Security, Medicare, Medicaid -- even Food Stamps -- are all federal entitlement programs.
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