radioactive

adjective ra·dio·ac·tive \ ˌrā-dē-ō-ˈak-tiv \

Updated on: 13 Apr 2018

Definition of radioactive

: of, caused by, or exhibiting radioactivity

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radioactively

adverb

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Examples of radioactive in a Sentence

Uranium and plutonium are radioactive.

Recent Examples of radioactive from the Web

Door seals, designed to prevent radioactive and other hazardous materials from seeping into the station, were missing.

— andrew jeong, WSJ, "South Korea Lacks Shelters, Equipment Needed in a Nuclear Attack," 2 Apr. 2018
The concern remains that countries with nuclear power plants might want to one day use that radioactive material to make nuclear weapons, as Iran was believed to be attempting.

— james osborne, San Antonio Express-News, "Perry fights to keep U.S. nuclear sector alive," 26 Mar. 2018
Advertisement After crashing into a military convoy carrying radioactive materials, Jessica's father, mother, and brother die, and Jessica falls into a months-long coma.

— refinery29.com, "How Did Jessica Jones Get Her Super Powers?," 9 Mar. 2018
In the years since the disaster and the immediate effort to stanch the release of radioactive material, officials have been working out how to decontaminate the site without unleashing more radiation into the environment.

— tim hornyak, Scientific American, "Clearing the Radioactive Rubble Heap That Was Fukushima Daiichi, 7 Years On," 9 Mar. 2018
If the government collapses, terrorists could steal a nuclear weapon or radioactive material that could be used in a dirty bomb.

— nicholas grossman, National Review, "The U.S. Needs to Rethink What Winning in Afghanistan Looks Like," 7 Feb. 2018
State and federal officials have downplayed the risk that the smoldering could reach the radioactive material.

— CBS News, "EPA announces $236M plan to clean up suburban St. Louis landfill," 1 Feb. 2018
A pool of water underneath the reactor had filled with radioactive material that could cause a mass steam explosion that would hit the rest of Europe, causing even more damage.

— terrell jermaine starr, The Root, "I Toured One of the Most Radioactive Places on Earth," 30 Jan. 2018
Jittery pilots may refuse to transport radioactive material.

— beth mole, Ars Technica, "Scientists racing to save vital medical isotopes imperiled by shabby reactors," 17 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radioactive.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.