Skip Navigation Archive: U.S. Department of Health and Human Services U.S. Department of Health and Human Services
Archive: Agency for Healthcare Research Quality
Archival print banner

This information is for reference purposes only. It was current when produced and may now be outdated. Archive material is no longer maintained, and some links may not work. Persons with disabilities having difficulty accessing this information should contact us at: Let us know the nature of the problem, the Web address of what you want, and your contact information.

Please go to for current information.


Allergy: An abnormally high sensitivity to certain substances, such as pollens or foods. Common signs of allergies may include sneezing, itching, and skin rashes.

Anesthesia: A drug administered for medical purposes that causes a partial or total loss of feeling.

Antibiotic: A drug, such as penicillin or streptomycin, that can destroy or prevent the growth of bacteria. Antibiotics are widely used to prevent and treat infectious diseases.

Benefit: Something that promotes or enhances well-being; an advantage.

Clinic: A facility, often associated with a hospital or medical school, devoted to the diagnosis and care of outpatients.

Complication: A disease, an accident, or a reaction that occurs during an illness and usually makes the illness worse.

Condition: A disease or physical problem.

Diagnosis: The act of identifying or determining the nature and cause of a disease or injury through evaluating the patient’s history, an examination, and a review of laboratory data.

Disease: An illness; sickness; ailment.

Elective Surgery: A surgery that is optional, not required

Emergency: A serious situation that happens unexpectedly and demands immediate action.

Generic Medicine: Drugs that have the same dosage, safety, quality, performance, and strength as a brand-name drug and are approved by the Food and Drug Administration. The color or flavor of a generic medicine may be different from the brand-name drug, but the active ingredient is the same. Generic drugs usually cost less than brand-name drugs.

Health History: A regularly updated record of a person's past and present health status.

Hospital: An institution that provides medical, surgical, or psychiatric care and treatment for the sick or the injured.

Medical Record: A file that contains a patient's medical history and care.

Medication/Medicine: A substance used in treating disease or illness.

Surgery: A procedure for remedying an injury, ailment, defect, or dysfunction.

Outpatient Surgery: A procedure in which the patient is not required to stay overnight in a hospital; also called same-day surgery.

Pharmacist: A person licensed to prepare and dispense drugs and medicines

Pharmacy: A place where drugs are sold; a drugstore.

Prescription: A direction written to a pharmacist for the preparation and use of a medicine.

Preventive Medical Test. Tests designed to rule out or avoid disease. For example, screening for high blood pressure and treating it before it causes serious health problems is an example of a preventive medical test.

Prognosis: A prediction of the probable outcome of a disease.

Risk: The possibility of suffering harm or loss; danger

Side Effect: An effect of a drug, chemical, or other medicine that is in addition to its intended effect, especially an effect that is harmful or unpleasant.

Specialist: A doctor who devotes attention to a particular class of diseases or patients.

Surgery: A procedure performed with instruments especially to repair damage or restore health.

Symptom: Something that indicates the presence of a disorder or disease.

Treatment: Administration of remedies to a patient or for a disease or injury.

Learn More

Guide to reliable health information.

Page last reviewed December 2012
Internet Citation: Glossary. Content last reviewed December 2012. Agency for Healthcare Research and Quality, Rockville, MD.


The information on this page is archived and provided for reference purposes only.


AHRQ Advancing Excellence in Health Care