1. Specific health care services and supplies for which the insurance plan or federal or state program will provide reimbursement for covered persons under the terms of the plan; these consist of a combination of mandatory and optional services stated in each plan. 2. Services for which supplemental medical insurance (SMI) pays, as defined and limited by statute. Covered services include most physician services, care in outpatient departments of hospitals, diagnostic tests, durable medical equipment, ambulance services, and other health services that are not covered by the hospital insurance program. Also called coverage or covered expenses.