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English definition of “quantum”

quantum

noun [C]     /ˈkwɒn.təm/ US  /ˈkwɑːn.t̬əm/ (plural quanta) specialized
the smallest amount or unit of something, especially energy: quantum theoryParticular theories and concepts in physicsWeighing and measuring
(Definition of quantum noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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