Glossary

Our plain-English glossary helps you make sense of the terms doctors often use.

A  |  B  |  C  |  D  |  E  |  G  |  H  |  L  |  M  |  N  |  O  |  P  |  R  |  S  |  T

Acid Reflux: A condition in which food or liquid leaks backwards from the stomach into the tube from the mouth to the stomach (the esophagus). Also known as gastroesophageal reflux disease, or GERD, the condition can irritate the esophagus, causing heartburn and other symptoms.

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

Anesthesia: A loss of feeling or awareness caused by drugs or other substances. Anesthesia keeps patients from feeling pain during surgery or other procedures. Local anesthesia is a loss of feeling in one small area of the body. Regional anesthesia is a loss of feeling in a part of the body, such as an arm or leg. General anesthesia is a loss of feeling and a complete loss of awareness that feels like a very deep sleep.

Antibiotic: A drug used to treat infections caused by bacteria and other microorganisms. Atrial Fibrillation: A heart rhythm disorder (arrhythmia) that usually involves a fast heart rate that is not regular.

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B 

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

Bipolar Disorder: A condition in which people go back and forth between periods of feeling very good (mania) and irritable or depressed. The change between mania and depression can occur quickly.

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C 

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

Co-morbidity: The presence of one or more diseases or disorders in addition to a primary disease or disorder.

Comparative Effectiveness: A type of health care research that compares the results of one approach for managing a disease to the results of other approaches. Comparative effectiveness usually compares two or more types of treatments, such as different drugs, for the same disease. Comparative effectiveness also can compare types of surgery or other kinds of medical procedures and tests.

Complication: A medical problem that occurs during a disease or after a procedure or treatment. The complication may be caused by the disease, procedure, or treatment or may be unrelated to them.

Condition: A health problem with certain characteristics or symptoms.

Congenital Heart Disease: A problem with the heart's structure and function as a result of abnormal heart development before birth.

Coronary Artery Disease: A narrowing of the small blood vessels that supply blood and oxygen to the heart. It is the leading cause of death in the United States for men and women.

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D 

Diabetes: Any of several diseases in which the kidneys make a large amount of urine. Diabetes usually refers to diabetes mellitus in which there is also a high level of glucose (a type of sugar) in the blood because the body does not make enough insulin or use it the way it should.

Diagnosis: The process of identifying a disease from its signs and symptoms using patient history, examination, and laboratory and other test results.

Disease: A disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency or imbalance, toxicity, or unfavorable environmental factor; illness; sickness; ailment.

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E 

Elective Surgery: A surgery that is optional and not required.

Electronic Health Record: A computerized record of patient health in a care delivery setting. Typically, the data collected are created by and for health professionals while providing treatment.

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

Estrogen: A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones.

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G 

Generic Drugs: Generic drugs are safe, effective, and approved by the U.S. Food and Drug Administration (FDA). They have the same dosage, safety, quality, performance, and strength as brand-name drugs. The color or flavor of a generic medicine may be different, but the active ingredient is the same. After the patent runs out on a brand-name drug, companies can apply to the FDA to make a generic copy of that drug. Generic drugs usually cost less than brand-name drugs.

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H 

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

Hepatitis B: A serious disease that affects the liver. It is caused by the hepatitis B virus. It ranges in severity from a mild illness, lasting a few weeks (acute), to a serious long-term (chronic) illness that can lead to liver disease or liver cancer.

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

Hysterectomy: Surgery to remove the uterus and, sometimes, the cervix. When the uterus and the cervix are removed, it is called a total hysterectomy. When only the uterus is removed, it is called a partial hysterectomy

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L 

Long-Term Care: Services that help meet the medical and nonmedical needs of people with a chronic illness or disability.

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M 

Medical Error: An unintended but preventable adverse effect of care, whether or not it is evident or harmful to the patient.

Medical Record: Documentation of a patient's medical history and care.

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

Morbidity: A disease or the incidence of disease within a population. Morbidity also refers to adverse effects caused by a treatment.

Mortality: The state of being mortal (destined to die). Mortality also refers to the death rate, or the number of deaths in a certain group of people in a certain period of time. Mortality may be reported for people who have a certain disease, live in one area of the country, or who are of a certain gender, age, or ethnic group.

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N 

Nursing Home: A place that gives care to people who have physical or mental disabilities and need help with activities of daily living (such as taking a bath, getting dressed, and going to the bathroom) but do not need to be in the hospital.

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O 

Outpatient Surgery: A surgical procedure in which the patient is not required to stay overnight in a hospital.

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P 

Pharmacist: A person licensed to prepare and give out (dispense) prescription drugs and medicines and who has been taught how they work, how to use them, and their side effects.

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

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

Privileges: A clinician's right to practice his or her profession, such as medicine or surgery, at a particular hospital or health care facility.

Prognosis: The likely outcome or course of a disease; the chance of recovery or recurrence.

Pulse Rate: The number of times the heart beats per minute.

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R 

Readmission: Being admitted to a hospital or health care facility after being treated and discharged for the same condition or as a result of a complication.

Recovery: Restoration or return to health from sickness.

Risk: The possibility of suffering harm or loss; danger.

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S 

Second Opinion: When a patient seeks the recommendation or differing point of view of a doctor or other clinician other than the one a patient has previously been seeing.

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 or other health care professional who is trained and licensed in a special area of practice. Examples of medical specialists include oncologists (cancer doctor) and hematologists (blood doctor).

Surgery: A procedure to remove or repair a part of the body or to find out whether disease is present; an operation.

Symptom: A sign or indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

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T 

Test Result: The conclusion or result of a particular test, performed on a particular specimen, such as a patient’s blood.

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

Treatment Option: A medicine or therapy to treat a problem. A treatment option may be a pill, a shot, exercise, operation, or a combination of things. Often, patients may have choices when there is more than one way to treat a health problem.

Treatment Plan: A road map or plan that a patient will follow on his or her path through treatment of a medical condition.

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For terms not included on this page, please visit the Medline Plus Medical Dictionary

Current as of August 2011
Internet Citation: Glossary. August 2011. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/patients-consumers/patient-involvement/ask-your-doctor/tips-and-tools/glossary.html