Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

Medical Dictionary


noun \-ˌwən-ˌthərt-ē-ˈwən\

Medical Definition of iodine–131

  1. :  a heavy radioactive isotope of iodine that has the mass number 131 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

Seen and Heard

What made you want to look up iodine–131? Please tell us where you read or heard it (including the quote, if possible).