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Meaning of “half-life” in the English Dictionary

"half-life" in British English

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half-lifenoun [C]

uk   /ˈhɑːf.laɪf/  us   /ˈhæf.laɪf/ specialized
the length of time needed for the radioactivity of a radioactive substance to be reduced by half
(Definition of half-life from the Cambridge Advanced Learner’s Dictionary & Thesaurus © Cambridge University Press)

"half-life" in American English

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half-lifenoun [C usually sing]

 us   /ˈhæfˌlɑɪf/
physics, earth science the amount of time needed for the radioactivity (= harmful form of energy) of a radioactive substance to be reduced by half
(Definition of half-life from the Cambridge Academic Content Dictionary © Cambridge University Press)
Translations of “half-life”
in Chinese (Simplified) (放射性物质的)半衰期…
in Chinese (Traditional) (放射性物質的)半衰期…
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