Definition of radioactive in English:


Line breaks: radio|active
Pronunciation: /ˌreɪdɪəʊˈaktɪv


  • Emitting or relating to the emission of ionizing radiation or particles: radioactive decay the water was radioactive
    More example sentences
    • They realized that the particles emitted by radioactive elements as they decay are in fact little bits of the atomic nuclei.
    • Radon decays to form tiny radioactive particles, some of which remain suspended in the air.
    • This three-year project was to lead to the discovery of the causes of radioactive emissions.



More example sentences
  • It is unstable, and scientists know that it radioactively decays by electron emission to Nitrogen 14, with a half life of 5730 years.
  • ‘There is likely to be an increase in radioactively contaminated metals and other radioactive sources entering the scrap supply chain,’ he said.
  • Those four iron isotopes are all radioactively stable.

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