Definition of caffeine
: a bitter alkaloid C8H10N4O2 found especially in coffee, tea, cacao, and kola nuts and used medicinally as a stimulant and diuretic
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Examples of caffeine in a Sentence
Her doctor told her to avoid caffeine.
Origin and Etymology of caffeine
German Kaffein, from Kaffee coffee, from French café
First Known Use: circa 1823
Other Biochemistry Terms
CAFFEINE Defined for English Language Learners
caffeine
playDefinition of caffeine for English Language Learners
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: a substance that is found especially in coffee and tea and that makes you feel more awake
CAFFEINE Defined for Kids
caffeine
playDefinition of caffeine for Students
: a substance found especially in coffee and tea that makes a person feel more awake
Medical Dictionary
Learn More about caffeine
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See words that rhyme with caffeine Spanish Central: Translation of caffeine Nglish: Translation of caffeine for Spanish speakers Britannica English: Translation of caffeine for Arabic speakers Britannica.com: Encyclopedia article about caffeine
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