Medical terms A–Z

Transdermal describes a medication delivery method in which a drug passes through unbroken skin into the bloodstream, often using a patch.

A substance being studied in the treatment of brain tumors.

Rarely whole blood any more: a donation is split into parts so each patient receives only the component that is missing.

Stroke symptoms that clear on their own within minutes or hours, carrying far more weight as a warning than their brevity suggests.

When the shaking appears matters far more than how bad it looks, because timing points to which part of the motor system is failing.

The word names a shape of damage rather than a single disease, so its causes run from pressure to infection to cancer.

A description rather than a diagnosis, telling a reader that a surface has been lost and something is stopping it from closing.

One of the commonest reasons for an antibiotic prescription, and a diagnosis that rests on symptoms rather than on a urine test alone.

A rash that behaves unlike most others: each welt lasts hours, fades without a trace, and reappears somewhere else.

A rehearsal for an infection the body has never met, arranged so that the real encounter is answered from memory.

The leg has to move blood uphill against gravity, and once the valves that stop it falling back give way, the vein stretches.

Not the same thing as dizziness or faintness, and the distinction narrows the list of possible causes faster than any test.

A rare, genetic disorder that is present at birth and has two or more of the following symptoms: Wilms tumor (a type of kidney cancer); little or no iris (the colored part of the eye); defects in…

Waldenstrom macroglobulinemia is a slow growing lymphoma marked by excess antibody production that can thicken the blood and impair circulation.

Food, alcohol and dozens of other drugs shift its effect, which is why the dose is set by blood test rather than by body weight.

In surgery, keeping a tissue, organ, or body part at body temperature after its blood suppy has been reduced or cut off.

In surgery, the time a tissue, organ, or body part remains at body temperature after its blood supply has been reduced or cut off but before it is cooled or reconnected to a blood supply.

A raised growth on the surface of the skin or other organ.

The vitamins that dissolve in water and leave in urine, so the body holds only a small working supply of most of them.

A peppery salad leaf grown in running water, repeatedly confused in older references with an unrelated plant of a similar name.

The total count says little on its own; which of the five types is raised or lowered is what points anywhere useful.

Removal of a triangular block of tissue with the abnormal area at its center, taking as little healthy tissue as safety allows.

A drug used to lessen the toxic effects of substances that block the action of folic acid, especially the anticancer drug methotrexate.

A rare, inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid and pituitary glands and the pancreas.

An inherited disorder marked by rapid aging that begins in early adolescence.

A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery.

A study that compares the complete DNA of people with a disease or condition to the DNA of people without the disease or condition.

A narrowed airway behaves like a reed instrument, and the note it plays says more about tightness than about which disease caused it.

A type of surgery used to treat pancreatic cancer.

A staging system for prostate cancer that uses ABCD.

WHO is the United Nations agency responsible for coordinating international public health efforts, setting health standards, and responding to global disease threats.

Vaccine made from whole tumor cells that have been changed in the laboratory.

A study that compares the complete DNA of people with a disease or condition to the DNA of people without the disease or condition.

A type of external radiation therapy used to treat patients who have cancer in the brain.

A type of external radiation therapy used to treat patients who have cancer in the brain.

Whooping cough spreads easily and causes severe, prolonged coughing fits, posing the greatest danger to infants and young children.

Surgery to cut out the cancer and some healthy tissue around it.

Trifolium pratense.

It has no bearing on medical care, a point obscured by the name living will, which is an advance directive rather than a will.

Wilms tumor is the most common kidney cancer in children, usually diagnosed before school age and often highly treatable.

The airway that leads from the larynx (voice box) to the bronchi (large airways that lead to the lungs).

A procedure used to mark a small area of abnormal tissue so it can be removed by surgery.

A device used to look at tissues in the esophagus, stomach, and intestines.

The last tooth to come in at the back of each side of the upper and lower jaws.

One faulty protein leaves blood cells unable to change shape, and three unrelated-looking problems follow from that single defect.

A mixture made from an extract of the calf thymus gland and enzymes (proteins that speed up chemical reactions in the body) from the papaya plant, the pancreas of cows, and the pancreas of pigs.

A registered nurse who has additional education and training in how to care for people who have a wound, an ostomy (surgery to create an opening in the abdomen for a new path for urine or stool), or…

The small, hollow, pear-shaped organ in a woman's pelvis.

The part that names the body part, and the piece that stays put while prefixes and endings change around it.

Skin closes over an injury within days, but the repaired area keeps rebuilding for months and never regains its original strength.

WS is an inherited disorder that produces signs of accelerated aging beginning in early adulthood, arising from a gene mutation affecting DNA repair.

A substance being studied in the treatment of several types of cancer.

The same beam that produces a picture at low dose destroys cancer cells at high dose, and only the amount and aiming differ.

A type of radiation therapy that uses high-energy radiation from x-rays to kill cancer cells and shrink tumors.

Xeloda is the brand name for capecitabine, an oral chemotherapy drug converted in the body into its active anticancer form.

An abbreviation for a chemotherapy combination used to treat colorectal cancer that has spread.

An abbreviation for a chemotherapy combination used to treat colorectal cancer that has spread.

A xenograft is tissue or an organ transplanted from a donor of one species into a recipient of a different species.

A genetic condition marked by an extreme sensitivity to ultraviolet radiation, including sunlight.

A picture of the body recorded on paper rather than on film.

A picture of the body recorded on paper rather than on film.

A type of x-ray in which a picture of the body is recorded on paper rather than on film.

Xerostomia is persistent dry mouth from reduced saliva, commonly caused by medications, radiation therapy, or an underlying gland disorder.

A substance that is being studied in the treatment of leukemia.

A substance being studied in the treatment of cancer.

A substance that is being studied in the treatment of cancer.

A substance that is being studied in the treatment of breast cancer.

A form of the anticancer drug paclitaxel combined with a protein called poliglumex that may have fewer side effects and work better than paclitaxel.

A radiolabeled monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment of other types of B-cell tumors.

A radiolabeled monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment of other types of B-cell tumors.

An herb native to islands in the South Pacific.

Named for the jaundice of its severe phase, though most infections never reach that stage and some produce no illness at all.

Yin and yang describe paired opposing forces in traditional Chinese thought, a framework still used to describe balance and imbalance in traditional Chinese medicine.

A substance that may be found in higher-than-normal amounts in the blood of patients with certain types of cancer and inflammatory diseases.

A substance that is being studied as a treatment for advanced prostate cancer and for pain caused by prostate cancer that has spread to the bone.

What a yoga study measures depends on the style tested, since a restorative class and a heated flow class share little beyond the name.

A tree native to West Africa.

A metal of the rare earth group of elements.

A radioactive form of the rare metal yttrium that is used in radiation therapy to treat some types of tumors.

A radiolabeled monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment of other types of B-cell tumors.

A brand name that never launched: the drug behind it survived, changed disease, and reached the market under another name.

An asthma tablet that blocks the receptor for leukotrienes, chemicals released during an allergic reaction that tighten the airways.

A drug used to prevent and to treat influenza virus infections.

A substance that is being studied in the treatment of acute myeloid leukemia (AML) and other types of cancer.

A substance that is being studied in the treatment of cancer.

A drug that is used to treat certain types of non-small cell lung cancer and is being studied in the treatment of other types of cancer.

A substance that is being studied in the treatment of prostate cancer.

A substance that has been studied in the treatment of several types of cancer.

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

Zestril is the brand name for lisinopril, a medication that lowers blood pressure by blocking a hormone that narrows blood vessels.

A monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment and detection of other types of B-cell tumors.

In traditional Chinese medicine, the overall pattern read from a person, which directs treatment more than the disease name does.

A cone snail venom peptide turned painkiller, which works only when delivered straight into the fluid around the spinal cord.

Zidovudine, known as AZT, was the first antiretroviral drug approved to treat HIV infection by blocking viral replication.

An asthma tablet that shuts down the enzyme making leukotrienes, rather than blocking the receptors those chemicals act on.

The white paste on a lifeguard's nose and in diaper cream, working as a physical barrier rather than as an absorbed drug.

The soluble salt that actually delivers the element, unlike the insoluble oxide, which sits on the skin and delivers none of it.

A drug used to reduce heart damage in women given doxorubicin for breast cancer that has spread.

An infusion that shuts down the cells dismantling bone, given as rarely as once a year in some conditions.

Zoledronic acid is an intravenous bisphosphonate used to treat cancer-related high blood calcium and to reduce fractures from bone metastases.