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English definition of “caffeine”

caffeine

noun [U]     /ˈkæf.iːn/
a chemical , found for example in tea and coffee , that is a stimulant (= something that makes people more active )Specific types of drugDrugs - general wordsSpecific medicines and drugs
(Definition of caffeine noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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