Online Medical Dictionary

Letter E

E. coli: Escherichia coli, a bacterium found in the colon, normally harmless but for the strain serotype O157:H7 which can cause food poisoning.
Ear Bones: The ossicles, the three smallest bones in the body, namely: the malleus, incus and stapes.
Ear Ringing: Tinnitus.
Earache: Pain experienced in the ear resulting from conditions located within the ear itself, the ear canal, or the external portion of the ear.
Eardrum: The tympanum, the membrane separating the middle and external ear.
Ebola Virus: A deadly virus, killing nearly 9 in 10 of those infected, causing massive internal bleeding with hemorrhagic fever.
Echocardiography: Diagnostic imaging that uses ultrasound waves to image the heart chambers, valves and surrounding structures, testing for pericarditis (inflammation), measuring cardiac output, and detecting other abnormalities or infections.
Echolalia: Involuntary oral repetition of a word or phrase just heard spoken; sometimes seen with schizophrenia and Tourette syndrome.
Echopraxia: Involuntary movement imitating of those of another person's; sometimes seen with schizophrenia and Tourette syndrome.
Eclampsia: An acute, life-threatening condition causing seizures in pregnant women, associated with hypertension, more common in first-time or younger mothers.
ECST: Abbreviation for exercise cardiac stress test, one of the most widely used cardiac screening tests.
Ectopic: Located out of place, not in the normal position.
Ectopic Pregnancy: A pregnancy that occurs outside of the uterus, most often occurring in the Fallopian tube.
Edema: The swell of soft tissues due to the accumulation of excess fluids beneath the skin or in a cavity.
Edentulism: Without teeth.
Edwards Syndrome: Also known as Trisomy 18 syndrome, this genetic condition causes roughly one in 3,000 children to be born with a partial or complete secondary 18th chromosome. Children born with Edwards syndrome have a very low chance of survival. Risk is known to increase with the age of the mother at the time of her delivery.
EEG: Abbreviation for electroencephalogram, a technique used to study the brain's electrical current.
Effacement: The thinning of the cervix occurring previous to and during dilation.
Efferent: That which carries away. An efferent artery or vessel carries blood away from the heart, as an efferent nerve carries impulses away from the central nervous system. Opposite of afferent.
Effusion: The outpouring of a fluid or the flow of molecules. A hemorrhagic effusion equates an outpouring of blood, as a pleural effusion involves an outpouring of pleural fluid.
EGD: Abbreviation for esophagogastroduodenoscopy.
Eidetic: Exceptionally vivid recall. Eidetic memory recalls in accuracy even the most minute of details. Eidetic comes from the German Eidetisch. Also called photographic memory.
Eisoptrophobia: An abnormal fear of reflective surfaces.
Ejection Fraction: The portion of blood pumped out of a full ventricle when the heart beats. Normally this equates to about two-thirds of the ventricle's blood. If the heart is diseased this fraction can fall to one third of the ventricle's held blood store. The ejection factor can be used to indicate cardiac disease or other conditions of the heart.
Elastic Fiber: A slender, flexible fiber found in connective tissue rife in elastin and protein.
Elastin: A spring-like protein composed of elastic fibers of connective tissue with the ability to coil and recoil, allowing for the elasticity observed in the skin, ligaments, tendons, blood vessels, intestines, heart and lungs.
Elbow Bursitis: Swelling of the olecranon bursa located at the elbow, incited by trauma or strain.
Elective Mutism: A total lack of speech believed to be incurred of the individual's own volition, often occurring after trauma or serious injury.
Elective Surgery: Surgery subject to the decision of the individual or their practitioner; non-urgent surgery.
Electrocardiogram: A non-invasive procedure used to measure and record the electrical activity occurring in the heart.
Electrocoagulation: A technique which utilizes electrical current to bring bleeding to cessation.
Electrogastrogram: A technique used to perceive and record the electrical current generated by the stomach muscle, as an electrocardiogram does of the heart.
Electrolarynx: A vibration-producing device acting to replace the function of the larynx to assist in the process of speech when an individual's biological larynx is unable to function, usually due to cancer.
Electrolyte: A substance, usually composed of acids, bases or salts, containing free ions with the ability to conduct electricity.
Electromyogram: A method used to observe the electrical activity of muscles to test for abnormalities. Also called a myogram.
Electron Beam Computerized Tomography (EBCT): A noninvasive method for detecting coronary artery disease, which measures the accumulation of calcium deposits obstructing the walls of coronary arteries.
Electrophysiology: The study of electric activity taking place in the body.
Electrosurgery: Utlization of a heat-generating device to remove tissue and bring bleeding to cessation through the action of burning or vaporizing the tissue.
Emboli: That which travels through the bloodstream, lodges in a blood vessel an obstructs flow.
Embolism: Non-surgical obstruction of a blood vessel by introducing a foreign substance or blood clot.
Embolization: A treatment that uses an emboli, or foreign substance, to block small blood vessels in order to halt the flow of blood to an area of the body. Embolization can be used to reduce the size of a tumour, commonly used in kidney or liver lesions; and to occlude various types of hemorrhage.
Embryo: The earliest stages of an organisms development, from fertilization to cell differentiations. Roughly two months after fertilization, the human embryo becomes the fetus.
Embryonal Carcinoma: A rare malignant germ cell tumour that develops in the testes or the ovaries, usually appearing around the age of puberty.
Emergency Medical Technician (EMT): A medical professional trained to provide emergency medical care.
Emesis: The act of vomiting.
Emetic: That which induces vomitting.
Emetophobia: An abnormal fear of vomiting.
Emphysema: A chronic obstructive pulmonary disease progressing over time, causing shortness of breath through the breakdown of alveoli, the lungs' air sacs. Emphysema is found to be associated with cigarette smoking.
Empyema: The accumulation of pus within an already existing cavity (an abscess occurs in a new-formed cavity) such as pleural cavity of the lung, the appendix, the uterus, the joints, gallbladder or brain.
EMSY Protein: A protein that has been shown to bind to the gene BRCA2 mutated in the familial forms of breast cancer and ovarian cancer, linking the pathway to sporadic forms of breast and ovarian cancers.
Enanthem: A rash occuring inside the body, such as inside the mouth.
Enate: Of the mother's side.
Encapsulated: Confined to a certain area.
Encephalomyelitis: Inflammation of the brain and spinal cord, usually caused by infections affecting the nercous system.
Encephalopathy: A broad term reffering to malfunction, disease or damage occurring in the brain, usually brought on by infections of the liver, kidney failure or anoxia.
Endocardium: The lining of the heart chambers.
Endochondral bone: A bone that develops within cartilage, partially or completely destroying and reabsorbing the cartillage.
Endocrine Gland: A hormone secreting gland. These include the thyroid, pituitary gland and the hypothalamus.
Endocrinology: The study of hormones.
Endocrinopathy: Disease of a hormone secreting gland, such as hyperthyroidism.
Endometrial Biopsy: A procedure which extracts a sample from the lining of the uterus to investigate infection or infertility.
Endometrial Cancer: Cancer of the uterus, occuring most often in women between over the age of 55, believed to be related to high extrogen levels.
Endometrial Hyperplasia: Excessive proliferation, or overgrowth, of the cells in the lining of the uterus.
Endometrioid Cyst: Cyst that forms in the ovaries as a result of endometriosis.
Endometriosis: The presence of cells endometrial-like cells, like those found in the uterus lining, in other locations, such as the Fallopian tubes, the intestines or pelvic cavity, causing a host of symptoms including pelvic and back pain and possible infertility.
Endometritis: Inflammation of the inner layer of the uterus.
Endometrium: The lining of the uterus.
Endorectal MRI: Magnetic resonance imaging (MRI) conducted from within the rectum, used to screen for prostate cancer.
Endorphin: An opioid chemical produced by the body to diminish pain perception.
Endoscopy: A general term describing examination of the body's interior, usually the stomach or intestines, by use of the lighted instrument the endoscope. The endoscope is usually inserted through one of the body's natural openings.
Endovaginal Ultrasound: An imaging test that utilizes ultrasound technology to examine the pelvic organs; used to detect ovarian cysts.
Enervate: The partial or complete removal of a nerve; also called a neurectomy.
Enteroplasty: Intestinal surgery, usually conducted to lengthen the bowel or to enlarge a constricted intestinal segment.
Enterospasm: Painful, recurring and irregular contraction of the intestine. Also called peristalsis.
Enucleation: Surgical removal of the eye, usually in response to an ocular tumour or other ocular disease. The ocular muscles are left intact and usually an ocular prosthesis (artificial eye) is inserted in the eye's place.
Enuresis: Involuntary urination, also refered to as bedwetting.
Enzyme: Proteins that catalyze a chemical reaction.
Epidermal: Regarding the epidermis.
Epidermis: The outer layer of cells composing the skin.
Epidermoid Carcinoma: A type of carcinoma marked by tumours composed of cells that often resemble the scales of fish. Epidermoid carcinoma is a malignancy that can occur in various organs - with varied manifestations, symptoms and prognosis - including the lungs, skin, mouth, tongue, prostate, vagina and bladder. Also known as squamous cell carcinoma.
Epidural Anesthetic: A regional anesthetic agent injected through a catheter into the epidural space, outside the dura mater but inside the spinal canal, administered to numb sensation or block the transmission of pain though nerve associated with the spinal cord.
Epidural Hematoma: A traumatic injury incurred by the brain wherein blood builds up between the dura mater and the skull.
Epiglottis: The flap covering the trachea, attached to the tongue, which functions to prevent food from entering the lungs as it is swallowed.
Epilepsy: A chronic neurological disorder marked by unpredictable, recurrent seizures, a result of the excessive neuronal activity taking place in the brain. In a large number of cases epilepsy can be maintained with proper medication.
Epistaxis: Nosebleed.
Epithelial Carcinoma: Cancer orignating in thecells lining an organ.
ER: Abbreviation for emergency room, endoplasmic reticulum, estrogen receptor and extended release.
Ergophobia: An abnormal fear of working and the workplace.
Eructation: To belch.
Erythroleukemia: Acute nonlymphocytic leukemia, a form of acute myeloid leukemia, which causes the production of large numbers of abnormal, immature red blood cells to emerge in the body.
Erythrophobia: An abnormal fear of blushing.
Erythroprosopalgia: An episodic syndrome of headaches, also termed cluster headache or migrainous neuralgia.
Esophageal Cancer: Malignant tumour development in the tissues of the esophagus, the risk of which is increased by long-term irritants such as smoking, high levels of alcohol consumption and esophagitis.
Esophageal Reflux: A condition that causes the stomach to regurgitate partially digested food back into the esophagus, in some cases the acid-rich food also reaches the breathing passages, causing inflammation and acidic damage.
Esophagectomy: Surgical removal of a portion of the esophagus.
Esophagitis: Inflammation of the esophagus.
Esotropia: Convergent orinternal strabismus (cross-eyed).
Estrogen: A hormone produced by the female ovaries, the deficiency of which can lead to osteoporosis.
Estrogen Replacement Therapy (ERT): A hormone replacement therapy aimed to treat or prevent the discomfort brought on by the depletion of estrogen and progesterone being produced by the body previous to, during or after menopause occurs. Also believed to be a preventative measure against the development of osteoporosis.
Etiology: The study of causation.
Eustachian Tube: The auditory tube, or pharyngotympanic tube, running from the middle ear to the nasopharynx, functioning to drain mucus from and equalize pressure between the middle ear. A blocking of the Eustachian tube, due to infection or allergens, can cause otitis media, middle ear inflammation.
Euthyroid: Normally functioning thyroid gland.
Exanthem: Rash.
Exanthem Subitum: Rash of sudden onset appearing in infants after a sudden high fever.
Excess Selenium: Selenosis, the chonic intake of higher than needed levels of selenium , found naturally in foods, which can cause reversible balding, intestinal distress, weakness and slowed mental response.
Excise: To remove completely, such as to excise a tumour by laser.
Excision: Removal by surgical means.
Exocrine Glands: Glands which secrete a substance by way of a duct, such as salivary glands, sweat glands and gastrointestinal tract glands.
Exophthalmos: An eyeball that protrudes, common in individuals with Graves' disease.
Explant: To remove an implanted device.
Exstrophy-Epispadias Complex: A rare congenital condition wherein the bladder develops inside out, outside of the abdominal wall, twice as likely to occur in males as in females, but correctable through a series of surgeries. Also called bladder exstrophy.
Extrauterine Pregnancy: A pregnancy that develops outside of the uterus, usually occurring in the Fallopian tube, most often not viable. Also termed ectopic pregnancy or eccysis.
Extravasate: To pass through or exude from vessel walls into the surrounding tissue.