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English definition of “radiation”


noun [U]     /ˌreɪdiˈeɪʃən/
HARMFUL ENERGY a form of energy that comes from a nuclear reaction and that in large amounts can be very dangerous : dangerously high levels of radiation radiation sickness Physics in general
HEAT energy from heat or light that you cannot see : solar / microwave radiationPhysics in general
(Definition of radiation noun from the Cambridge Learner's Dictionary © Cambridge University Press)

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