half-life noun - Definition, pictures, pronunciation and usage notes | Oxford Advanced American Dictionary at OxfordLearnersDictionaries.com

Definition of half-life noun from the Oxford Advanced American Dictionary

half-life

noun

[countable]

1(physics) the time taken for the radioactivity of a substance to fall to half its original value

2(chemistry) the time taken for the concentration of a reactant to fall to half of its original value in a chemical reaction

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