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Glossary - D

This glossary explains terms in the Medicare program.



The amount you must pay for health care or prescriptions before Original Medicare, your prescription drug plan, or your other insurance begins to pay.

Deemed status

A provider or supplier earns this when they have been accredited by a national accreditation program (approved by the Centers for Medicare & Medicaid Services) that they demonstrate compliance with certain conditions.


Special projects, sometimes called "pilot programs" or "research studies," that test improvements in Medicare coverage, payment, and quality of care. They usually operate only for a limited time, for a specific group of people, and in specific areas.

Dental coverage

Benefits that help pay for the cost of visits to a dentist for basic or preventive services, like teeth cleaning, X-rays, and fillings.

Department of Health and Human Services (HHS)

The federal agency that oversees CMS, which administers programs for protecting the health of all Americans, including Medicare, the Marketplace, Medicaid, and the Children’s Health Insurance Program (CHIP).

Diagnostic mammogram

An X-ray exam of the breast in a woman who either has a breast problem or has had a change show up on a screening mammogram.

Diethylstilbestrol (DES)

A drug given to pregnant women from the early 1940s until 1971 to help with common problems during pregnancy. The drug has been linked to cancer of the cervix or vagina in women whose mother took the drug while pregnant.

DME Medicare Administrative Contractor (MAC)

A private company that contracts with Medicare to pay bills for durable medical equipment.

Drug list

A list of prescription drugs covered by a prescription drug plan or another insurance plan offering prescription drug benefits. This list is also called a formulary.

Durable medical equipment

Certain medical equipment, like a walker, wheelchair, or hospital bed, that's ordered by your doctor for use in the home.

Durable power of attorney

A legal document that names someone else to make health care decisions for you. This is helpful if you become unable to make your own decisions.

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This glossary explains terms in the Medicare program, but it isn't a legal document. The official Medicare program provisions are found in the relevant laws, regulations, and rulings.