Definition of radioactivity in English:


Line breaks: radio|activ¦ity
Pronunciation: /ˌreɪdɪəʊakˈtɪvɪti


[mass noun]
  • 1The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
    More example sentences
    • Early studies of radioactivity revealed that certain atomic nuclei were naturally radioactive.
    • They may also interact with nonmedical regulations, such as limits on electromagnetic emissions or radioactivity.
    • What makes dirty bombs particularly troublesome is that radioactivity, like fire, is something we deal with on a daily basis.
  • 1.1Radioactive substances, or the radiation emitted by these: an escape of radioactivity
    More example sentences
    • Small amounts of radioactivity escaped into the atmosphere.
    • The lack of safeguards is leaving thousands of children across central Scotland at risk of thyroid cancer following an escape of radioactivity.
    • They are comparing sediment taken from the Humber estuary - unpolluted by radioactivity - with other samples which contain the substance.

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