NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,922 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (...TEH-truh-i-oh-doh-THY-roh-neen)
- A hormone that is made by the thyroid gland and contains iodine. L-3,5,5’-tetraiodothyronine increases the rate of chemical reactions in cells and helps control growth and development. L-3,5,5’-tetraiodothyronine can also be made in the laboratory and is used to treat thyroid disorders. Also called T4, thyroxin, and thyroxine.