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.
Recent Examples of caffeine from the Web
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Toxicology tests showed the presence of barbiturates, caffeine and lorazepam, also known as Ativan, for relief of anxiety.
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Toxicology tests showed the presence of barbiturates, caffeine and lorazepam, also known as Ativan, for relief of anxiety.
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Toxicology tests showed the presence of barbiturates, caffeine and lorazepam, also known as Ativan, for relief of anxiety.
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Toxicology tests showed the presence of barbiturates, caffeine and lorazepam, also known as Ativan, for relief of anxiety.
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Going back to the 1940s, researchers have exposed spiders to caffeine, amphetamines, LSD and other drugs, attracting plenty of media attention along the way.
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Created by Cronut inventor Dominique Ansel, cold-brew soft-serve is a caffeine lover's dream.
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Byrne asked, referencing incidents of caffeine overdoses.
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Sometimes cutting back on caffeine and sugar can help lift your mood.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'caffeine'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of caffeine
German Kaffein, from Kaffee coffee, from French café
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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