radioisotope

noun

ra·​dio·​iso·​tope ˌrā-dē-ō-ˈī-sə-ˌtōp How to pronounce radioisotope (audio)
: a radioactive isotope
radioisotopic
ˌrā-dē-ō-ˌī-sə-ˈtä-pik How to pronounce radioisotope (audio)
-ˈtō-
adjective
radioisotopically
ˌrā-dē-ō-ˌī-sə-ˈtä-pi-k(ə-)lē How to pronounce radioisotope (audio)
adverb

Examples of radioisotope in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Oklo also promises to produce special radioisotopes for medical and industrial end users. — Ian Dexter Palmer, Forbes.com, 4 May 2026 The company focuses on producing radioisotopes used in nuclear medicine. — Raul Trey Lopez, San Antonio Express-News, 12 Mar. 2026 Turning waste into power At the heart of the project is a radiovoltaic device that uses radioisotopes such as Strontium-90 to generate electricity. — Aamir Khollam, Interesting Engineering, 17 June 2026 The spacecraft runs on a radioisotope thermoelectric generator — a device that converts heat from decaying plutonium into electricity. — Willem Marx, NPR, 19 Apr. 2026 See All Example Sentences for radioisotope

Word History

Etymology

International Scientific Vocabulary

First Known Use

1938, in the meaning defined above

Time Traveler
The first known use of radioisotope was in 1938

Rhymes for radioisotope

See All Rhymes for radioisotope

Browse Nearby Words

radioimmunoassay
radioisotope
radioisotopic
See all Nearby Words

Cite this Entry

“Radioisotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radioisotope. Accessed 7 Jul. 2026.

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Kids Definition

radioisotope

noun
ra·​dio·​iso·​tope ˌrād-ē-ō-ˈī-sə-ˌtōp How to pronounce radioisotope (audio)
: a radioactive isotope

Medical Definition

More from Merriam-Webster on radioisotope

Britannica.com: Encyclopedia article about radioisotope

Last Updated: - Updated example sentences
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