Medical terms A–Z

A monoclonal antibody that is being studied in the treatment of some types of cancer.

A drug used together with other drugs to prevent and control nausea and vomiting caused by cancer treatment.

Emesis is the forceful expulsion of stomach contents through the esophagus and mouth; it is another term for vomiting.

Anything that brings on vomiting, whether given deliberately, produced by a disease, or arriving as a side effect.

Describes a substance that causes vomiting.

EMF refers to the electric and magnetic fields surrounding power lines and electronic devices, whose long term health effects remain an active research question.

An anticancer drug that belongs to the family of drugs called antimetabolites.

A substance found in certain plants, including rhubarb.

The trouble is not only getting air in; damaged lungs have lost the springiness that used to push it back out.

The fact that decides everything is whether a wave carries enough energy to knock electrons out of atoms, making it ionizing.

Enalapril is an ACE inhibitor that relaxes blood vessels, used broadly to treat high blood pressure and heart failure.

Encapsulated describes an abnormal growth or collection that is contained within a thin surrounding layer of tissue rather than spreading into nearby structures.

Confusion, drowsiness or a change in personality can all be the visible face of a chemical problem somewhere else in the body.

An enchondroma is a benign cartilage growth within bone, most often found in the small bones of the hand and often discovered incidentally.

Endocarditis is inflammation of the heart's inner lining and valves, most often from bacterial infection reaching the bloodstream and heart tissue.

A procedure in which the mucous membrane of the cervical canal is scraped using a spoon-shaped instrument called a curette.

Signals released straight into the bloodstream reach every tissue, so a gland the size of a pea can change what the whole body does.

Cancer that occurs in endocrine tissue, the tissue in the body that secretes hormones.

A pancreatic cell that produces hormones (e.g., insulin and glucagon) that are secreted into the bloodstream.

Ductless glands drop their messengers straight into the blood, so a signal made in one place acts on organs far away.

A tumor that is found in endocrine tissue but does not make extra hormones.

Hormones travel everywhere, so this specialty is defined by the messenger rather than by a single organ or region of the body.

Produced inside an organism or cell.

Having to do with the endometrium (the layer of tissue that lines the uterus).

A procedure in which a sample of tissue is taken from the endometrium (inner lining of the uterus) for examination under a microscope.

Endometrial cancer arises in the lining of the uterus and typically announces itself through abnormal vaginal bleeding, especially bleeding after menopause.

Abnormal cell growth in the endometrium (the lining of the uterus).

An abnormal overgrowth of the endometrium (the layer of cells that lines the uterus).

A benign condition in which tissue that looks like endometrial tissue grows in abnormal places in the abdomen.

The endometrium is the inner lining of the uterus that thickens and sheds each menstrual cycle and supports a pregnancy if one occurs.

A procedure in which a probe that sends out high-energy sound waves is inserted into the rectum.

Endorphins are natural opioid peptides the body releases to reduce pain signaling and contribute to a sense of well-being.

A camera on the end of a steerable tube, and increasingly the instrument that performs the operation rather than merely finding it.

A procedure in which an endoscope is inserted into the body.

A procedure that uses an endoscope to examine the inside of the body.

A procedure in which an endoscope is inserted into the body.

A substance being studied in the treatment of cancer.

The single layer of flat cells lining every vessel, acting as a non-stick surface and as a control panel for blood flow.

A drug that blocks the hormone endothelin and may prevent prostate cancer from spreading to the bones.

Fixed before the first participant enrolls, it settles in advance what will count as the treatment working and what will not.

An enema introduces liquid into the rectum and lower bowel, used to relieve constipation, empty the bowel before a procedure, or deliver medication.

In biology, the state at which the number of calories eaten equals the number of calories used.

A group of hands-on and hands-near practices built on a life force that measurement has never found.

A form of complementary and alternative medicine based on the belief that a vital energy flows through the human body.

A type of chamomile plant with daisy-like white flowers that is found in Europe, North America, and Argentina.

One species among many sold as lavender, and the one whose oil is meant when a recipe or a study says lavender.

An anticancer drug that increases the effectiveness of fluorouracil.

A food that has nutrients added back that were lost during processing.

A doctor who specializes in treating diseases of the ear, nose, and throat.

A form of nutrition that is delivered into the digestive system as a liquid.

A health professional trained in the care of persons with stomas, such as colostomies or urostomies.

In medicine, the removal of an organ or tumor in such a way that it comes out clean and whole, like a nut from its shell.

A virus that has an outer wrapping or envelope.

Environmental tobacco smoke combines smoke exhaled by smokers with smoke released directly from burning tobacco, inhaled involuntarily by others nearby.

A substance being studied in the treatment of certain types of cancer, including non-Hodgkin lymphoma, breast, colon, lung, ovarian, and prostate.

An enzyme is a specialized protein that speeds up a specific chemical reaction in the body without being consumed or permanently changed by it.

This laboratory test, commonly abbreviated ELISA, uses enzyme-linked antibodies bound to a solid surface to detect and measure a specific substance in a fluid sample.

Its weapons cut both ways: the granule proteins that damage parasites also injure airway and skin tissue in allergic disease.

A number on a blood report rather than something a person feels, and its size shapes how far the search for a cause goes.

A thin membrane that lines the fluid-filled spaces in the brain and spinal cord.

A cell that forms the lining of the fluid-filled spaces in the brain and spinal cord.

A type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain).

A tumor growing from the lining of the brain's fluid spaces, able to shed cells into that fluid and settle further down.

A shrub native to China and India.

Outbreak investigation, risk factor studies and the evaluation of public health measures all sit with this population level specialist.

Counting cases, comparing exposed and unexposed groups, and testing whether an intervention changes the numbers are the core tasks of the discipline.

A layer with no blood supply of its own, rebuilt continuously from below and shed from above roughly once a month.

Cancer that begins in squamous cells (thin, flat cells that look like fish scales).

A group of chronic skin disorders in which fluid-filled blisters form on the skin and mucosa (the moist, inner lining of some organs and body cavities).

The epididymis is a tightly coiled tube behind each testicle where sperm cells complete maturation and are stored before ejaculation.

A catheter left sitting in the space outside the cord is what lets the block be topped up, adjusted or deepened.

An injection of an anesthetic drug into the space between the wall of the spinal canal and the covering of the spinal cord.

Not one disease but a shared endpoint with dozens of causes, from a birth injury to a scar, a gene or a tumor.

The medical name for a nosebleed, and one of the few bleeding sites where the exact spot decides how easily it stops.

The most common receptor result in breast cancer, and the one that opens the door to hormone-blocking treatment taken over years.

A negative result narrows the options rather than worsening them outright, and it is the first of the three markers behind the triple-negative label.

A substance that is being studied as a treatment for cancer.

The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide.

Often the first visible sign of narrowed arteries elsewhere, which is why it is treated as a cardiovascular finding and not only a sexual one.

An erection is the firming of erectile tissue as it fills with blood, a physiologic response involving structures in both male and female anatomy.

Vitamin D2, produced by shining ultraviolet light on yeast or mushrooms, and the one form of vitamin D the body cannot make.

A daily tablet that switches off a growth signal on the cancer cell surface, working best where one specific mutation is present.

ERMS is an abbreviation for embryonal rhabdomyosarcoma, the most common soft tissue cancer diagnosed in infants and young children.

ERT supplies estrogen to postmenopausal women or those without ovaries, and is distinguished from combined regimens that also include progesterone.

A procedure in which a probe that sends out high-energy sound waves is inserted into the rectum.

Pressing on the area is the quickest test, since redness from widened vessels fades under a finger and bleeding into skin does not.

Stripped of a nucleus and packed with hemoglobin, this cell trades any ability to repair itself for maximum oxygen carrying capacity.

A condition in which immature red blood cells (erythroid cells) in the bone marrow are abnormal in size, shape, organization, and/or number.

A condition in which immature red blood cells (erythroid cells) in the bone marrow are abnormal in size, shape, organization, and/or number.

Cancer of the blood-forming tissues in which large numbers of immature, abnormal red blood cells are found in the blood and bone marrow.

An abnormal patch of red and white tissue that forms on mucous membranes in the mouth and may become cancer.

An abnormal patch of red tissue that forms on mucous membranes in the mouth and may become cancer.

The kidney doubles as an oxygen meter, releasing this hormone whenever the blood passing through it carries less oxygen than it should.

The mirror image half of an older drug, isolated because that half carries nearly all of the activity while its twin adds little.

Esomeprazole is a proton pump inhibitor that reduces stomach acid production to treat acid reflux and ulcer related conditions.

The adjective attached to anything concerning the swallowing tube, from reflux and strictures to cancers and speech after surgery.

Lacking the outer wrapping that surrounds other digestive organs, the esophagus lets a tumor reach neighboring structures early.

The backward flow of stomach acid contents into the esophagus (the tube that connects the mouth to the stomach).

Speech produced by trapping air in the esophagus and forcing it out again.

A tube placed in the esophagus to keep a blocked area open so the patient can swallow soft food and liquids.