Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

  

English definition of “radioactive”

radioactive

adjective     /ˌreɪ.di.əʊˈæk.tɪv/ US  /-oʊ-/
having or producing the energy that comes from the breaking up of atoms: Uranium is a radioactive material. radioactive wasteRadiation and radioactivity
(Definition of radioactive adjective from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of radioactive

Definitions of “radioactive” in other dictionaries

Word of the Day

work out

to exercise in order to improve the strength or appearance of your body

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More