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English definition of “radiation”

radiation

noun [U]    /ˌreɪ·diˈeɪ·ʃən/
physics energy in the form of waves or particles (= any of the smallest pieces of matter that make up atoms): Residents argued that electromagnetic radiation emitted by the radar towers might pose a health hazard.
(Definition of radiation noun from the Cambridge Academic Content Dictionary © Cambridge University Press)
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