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Synonyms

radioactive

American  
[rey-dee-oh-ak-tiv] / ˌreɪ di oʊˈæk tɪv /

adjective

  1. Physics, Chemistry. of, relating to, exhibiting, or caused by radioactivity.

    A pressing issue in post-Soviet Russia is safe long-term storage of radioactive waste, from both military and civilian applications.

  2. relating to or being a person, topic, or matter that is likely to provoke intense negative reactions or disagreement.

    The option of raising taxes to fund these expenditures is a politically radioactive approach that a majority of state policymakers have avoided.


radioactive British  
/ ˌreɪdɪəʊˈæktɪv /

adjective

  1. exhibiting, using, or concerned with radioactivity

"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

radioactive Cultural  
  1. A descriptive term for a material made up of atoms in which radioactivity occurs.


Usage

What does radioactive mean? Radioactive describes something that exhibits or is caused by radioactivity. If something is radioactive, it emits radiation, which usually takes the form of electromagnetic waves or fast-moving elementary particles, such as protons or neutrons.While low doses of radiation are usually harmless, being exposed to large amounts of radiation will most likely kill you. For this reason, highly radioactive materials are often considered very dangerous and will only be handled by experts.Example: The radioactive waste produced by nuclear power plants can damage the environment. 

Other Word Forms

  • nonradioactive adjective
  • radioactively adverb
  • unradioactive adjective

Etymology

Origin of radioactive

First recorded in 1895–1900; radio- + active

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Australia’s government is investing about $5.6 billion in Stirling for things like a training center, housing, improvements to the submarine pier, a facility to handle radioactive waste, and power.

From The Wall Street Journal

On the downside, though, researchers at North Carolina State University report that avocados are radioactive.

From MarketWatch

Some highly radioactive sources also went missing temporarily.

From The Wall Street Journal

Nuclear power also produces radioactive waste; disposing of it can be costly and comes with environmental risks.

From BBC

The disaster spread nuclear contaminants across Europe, and authorities have since built a giant dome to try to contain radioactive materials there.

From BBC