radioactivity noun

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/ˌreɪ.di.əʊ.ækˈtɪv.ɪ.ti/

/-oʊ.ækˈtɪv.ə.t ̬i/ n [U]

Definition

•

the quality that some atoms have of producing energy, which can be very harmful to health

•

the energy produced by atoms in this way

A dangerous amount of radioactivity was released into the environment last month.

(Definition of radioactivity noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

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Synonyms and related words:

alpha particle
background radiation
beta particle
gamma radiation
gamma ray
half-life
irradiate
radiation
radioactive

Topic: Radiation and radioactivity

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