Main Entry: iodine–131 Pronunciation: -"w&n-"th&rt-E-'w&n Function: noun : a heavy radioactive isotope of iodine that has the mass number131 and a half-life of eight days, emits beta particles and gamma rays, and is used especially in the form of its sodium salt in the diagnosis of thyroid disease and the treatment of goiter
iodine-131n. A radioisotope of iodine that emits beta and gamma rays, has a half-life of 8.05 days, and is used as a tracer in thyroid studies and as therapy in hyperthyroidism and thyroid cancer.
