half-life Definition in the Cambridge English Dictionary

Definition of “half-life” - English Dictionary

"half-life" in American English

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half-lifenoun [C usually sing]

 us   /ˈhæfˌlɑɪf/
physics, earth science the ​amount of ​timeneeded for the ​radioactivity (= ​harmfulform of ​energy) of a ​radioactivesubstance to be ​reduced by ​half
(Definition of half-life from the Cambridge Academic Content Dictionary © Cambridge University Press)

"half-life" in British English

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half-lifenoun [C]

uk   /ˈhɑːf.laɪf/  us   /ˈhæf-/ specialized
the ​length of ​timeneeded for the ​radioactivity of a radioactivesubstance to be ​reduced by ​half
(Definition of half-life from the Cambridge Advanced Learners Dictionary & Thesaurus © 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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