radioactive isotope


An isotope having an unstable nucleus that decomposes spontaneously by emission of a nuclear electron or helium nucleus and radiation, thus achieving a stable nuclear composition.

Nearby words

  1. rectovesical pouch,
  2. rectovesical septum,
  3. rectrices,
  4. rectricial,
  5. rectrix,
  6. rectus,
  7. recumbent,
  8. recumbent bicycle,
  9. recuperate,
  10. recuperation

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.