Glossary of Medical Terms

The muscular tube through which food passes from the throat to the stomach.

The distance red blood cells travel in one hour in a sample of blood as they settle to the bottom of a test tube. The sedimentation rate is increased in inflammation, infection, cancer, rheumatic diseases, and diseases of the blood and bone marrow. Also called erythrocyte sedimentation rate and sedimentation rate.

The scented liquid taken from certain plants using steam or pressure. Essential oils contain the natural chemicals that give the plant its “essence” (specific odor and flavor). Essential oils are used in perfumes, food flavorings, medicine, and aromatherapy.

An increased number of thrombocytes (platelets) in the blood, without a known cause. Also called essential thrombocytosis.

An increased number of thrombocytes (platelets) in the blood, without a known cause. Also called essential thrombocythemia.

An herbal tea mixture that contains burdock root, Indian rhubarb root, sheep sorrel, and slippery elm bark. It has been claimed to remove toxins from the body, make the immune system stronger, relieve pain, control diabetes, treat AIDS, reduce tumor size, increase cancer survival, and improve quality of life. No clinical trial using Essiac in humans has been reported in a peer-reviewed, scientific journal, and the FDA has not approved the use of Essiac for the treatment of any medical conditions.

A chemical substance made when an acid and an alcohol combine and water is removed. Esters are found in essential oils (scented oils that come from plants).

A form of estrogen that may have fewer side effects than other forms. Esterified estrogens are used to treat some types of cancer, including prostate cancer. They are also used to treat the symptoms of menopause, (such as hot flashes, vaginal dryness, or heavy and painful bleeding) and osteoporosis (loss of bone mass). It is a type of drug called hormone therapy.

A rare type of cancer that forms in the tissues of the upper part of the nasal cavity (space inside the nose). This area is near the bone that separates the nasal cavity from the brain. These tissues are involved in the sense of smell. Esthesioneuroblastoma may spread from the nasal cavity to the bone around the eyes, the sinuses, the front part of the brain, or the lymph nodes in the neck. It is the most common type of nasal cavity tumor in children, especially in teens. Also called olfactory neuroblastoma.

A form of the hormone estrogen.