noun /ˌreɪdiˈeɪʃən,ɹaɪ.diˈaɪ.ʃən/
a) The shooting forth of anything from a point or surface, like the diverging rays of light; as, the radiation of heat.<! material copied from Websters Revised Unabridged Dictionary (1913)
b) The process of radiating waves or particles.
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