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radiation

noun
     
Related topics: Physics, Power
ra‧di‧a‧tion [uncountable]
1TPHP a form of energy that comes especially from nuclear reactions, which in large amounts is very harmful to living things:
An accident at the power station could result in large amounts of radiation being released.
a lethal dose of radiation
2TP energy in the form of heat or light that is sent out as waves that you cannot see:
Sun creams work by blocking harmful ultraviolet radiation.

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