Medical Glossary Index:

E

Eardrum- a thin, oval-shaped membrane that separates the inner ear from the outer ear and is responsible for transmitting sound waves

ECG (sometimes called an EKG)- an electrocardiogram, which is a record of the electrical impulses that trigger the heartbeat; used to diagnose heart disorders

Echocardiogram- an image of the heart that is created by high-frequency (ultrasound) sound waves

Eclampsia- a serious condition that occurs in late pregnancy, characterized by seizures in the woman

Ectopic- occurring at an abnormal position or time

Eczema- inflammation of the skin, usually causing itchiness and sometimes blisters and scaling; may be caused by allergies, but often occurs for no apparent reason

Edema- abnormal buildup of fluid in the body, which may cause visible swelling

EEG- see Electroencephalography

Elective- describes a treatment or procedure that is not urgent and can be arranged at the patient’s convenience

Electroencephalography- a procedure for recording the electrical impulses of brain activity

Embolism- the blockage of a blood vessel by an embolus - something previously circulating in the blood (such as a blood clot, gas bubble, tissue, bacteria, bone marrow, cholesterol, fat, etc)

Embryo- a term used to describe a child in the womb from fertilization to 8 weeks following fertilization

Emetic- a substance that causes vomiting; used to treat some cases of poisoning and drug overdose

Emphysema- a chronic disease in which the small air sacs in the lungs (the alveoli) become damaged; characterized by difficulty breathing

Encephalitis- inflammation of the brain, usually caused by a virus; may be very mild and barely noticeable, but is usually serious and can progress from headache and fever to hallucinations, paralysis, and sometimes coma

Endarterectomy- surgery performed to remove the lining of an artery that has been narrowed by fatty tissue buildup

Endemic- describes a disease that is always present in a certain population of people

Endocarditis- inflammation of the inner lining of the heart, usually the heart valves; typically caused by an infection

Endocardium- the inner lining of the heart

Endocrine gland- a gland that secretes hormones into the bloodstream

Endogenous- arising from inside of the body

Endometrial polyp- a growth (usually noncancerous) occurring on the lining of the uterus

Endometriosis- a condition in which fragments of the endometrium are found in other pelvic organs

Endometrium- the membrane that lines the uterus

Endophthalmitis- inflammation of the inside of the eye

Endorphin- a group of chemicals produced in the brain that reduce pain and positively affect mood

Endoscope- a lighted instrument used to view the inside of a body cavity

Endothelium- the layer of flat cells that lines the blood and lymph vessels, the heart, and other structures in the body

Endotracheal tube- a plastic tube that is fed down into the trachea through the mouth or nose to supply oxygen to a person who is not breathing properly

Enteritis- inflammation of the small intestine, usually causing diarrhea

Enterobiasis- infestation by a pinworm

Enuresis- the medical term for wetting the bed

Enzyme- a chemical, originating in a cell, that regulates reactions in the body

Epidemic- a term used to describe a disease that is rare then suddenly affects more people than usually expected

Epidermis- the outer layer of the skin

Epididymis- a long, coiled tube, exiting from the back of the testicle, in which sperm mature

Epidural anesthesia- a method of pain relief in which a painkilling drug is
injected into the space surrounding the spinal cord to block sensations in the
abdomen and lower body

Epilepsy- a disorder of the nervous system in which abnormal electrical activity in the brain causes seizures

Epinephrine- a hormone produced by the adrenal glands in response to stress, exercise, or fear; increases heart rate and opens airways to improve breathing; also called adrenaline

Episcleritis- a patch of inflammation on the outer layer of the white of the eye

Episiotomy- a surgical procedure in which an incision is made in the tissue between the vagina and anus to prevent tearing of this tissue during childbirth

Epithelium- the layer of cells that covers the body and lines many organs

Epstein-Barr virus- a virus that is the cause of mononucleosis and is involved in Burkitt’s lymphoma

Erysipelas- an infection caused by streptococci bacteria; characterized by fever and rash

Erythema- redness of the skin

Erythrocyte- a red blood cell

Erythrocyte sedimentation rate- a measure of the time it takes for red blood cells to collect at the bottom of a sample of blood; an elevated rate may mean that there is inflammation somewhere in the body

Erythroplakia- red patches in the mucous membranes of the mouth, throat, or voice box (larynx) that can become cancerous; risk factors include smoking pipes
and chewing tobacco

Esophageal spasm- irregular contractions of the muscles in the esophagus,
which lead to difficulty swallowing

Esophageal varices- swollen veins in the lower esophagus and possibly the upper part of the stomach; can cause vomiting of blood and passing of black stool

Esophagus- a tube-shaped canal in the digestive tract, connecting the throat to
the stomach

Estrogen- a group of hormones (produced mainly in the ovaries) that are necessary for female sexual development and reproductive functioning

Estrogen replacement therapy- treatment with synthetic estrogen drugs to relieve symptoms of menopause and to help protect women against osteoporosis
and heart disease

Eustachian tube- the tube that connects the middle ear and the back of the nose, draining the middle ear and regulating air pressure

Euthanasia- painlessly ending the life of a patient with an incurable disease who requests to die

Excision- the surgical removal of diseased tissue

Excretion- the process by which the body rids itself of waste

Exercise stress test- the monitoring of the heart during strenuous exercise, usually on a treadmill or exercise bicycle, to evaluate how the heart responds to stress

Exercise thallium test- an imaging test performed during and after an exercise stress test to evaluate functioning of the heart muscles

Exogenous- arising from outside of the body

Expectorant- a medication used to promote the coughing up of phlegm from the respiratory tract

Extensor muscle- a muscle that causes a joint or limb to straighten

External version- external repositioning of the fetus in the womb to the correct birth position

Extracorporeal shock wave lithotripsy- a procedure performed to destroy kidney stones using external shock waves

Extradural anesthesia- injection of an anesthetic into the space outside the dura mater, the fibrous membrane that envelops the spinal cord