[ rey-dee-oh-ahy-suh-tohp ]
/ ˌreɪ di oʊˈaɪ səˌtoʊp /


a radioactive isotope, usually artificially produced: used in physical and biological research, therapeutics, etc.

Origin of radioisotope

First recorded in 1940–45; radio- + isotope

OTHER WORDS FROM radioisotope

ra·di·o·i·so·top·ic [rey-dee-oh-ahy-suh-top-ik], /ˌreɪ di oʊˌaɪ səˈtɒp ɪk/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for radioisotope

/ (ˌreɪdɪəʊˈaɪsətəʊp) /


an isotope that is radioactive

Derived forms of radioisotope

radioisotopic (ˌreɪdɪəʊˌaɪsəˈtɒpɪk), adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for radioisotope

[ rā′dē-ō-īsə-tōp′ ]


A naturally or artificially produced radioactive isotope.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for radioisotope

[ rā′dē-ō-īsə-tōp′ ]

A radioactive isotope of a chemical element. Carbon 14 and radon 222 are examples of naturally occurring radioactive isotopes.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.