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English definition of “free radical”

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free radical

noun [C often plural] uk   specialized us  
a molecule that has an extra electron and therefore reacts very easily with other molecules: Free radicals have been implicated in cancer and many other serious diseases.
Translations of “free radical”
in Chinese (Traditional) 自由基,遊離基…
in Chinese (Simplified) 自由基,游离基…
(Definition of free radical from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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