HALF-LIFE


Meaning of HALF-LIFE in English

noun [ C ]

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

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.