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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Caffeine is a stimulant and can disrupt a child’s normal sleep rhythm.
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By Jennifer R. Statham for AL.com Many depend on a jolt of caffeine each morning to get up and going.
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Yes, there is caffeine, which stimulates urination, but the amount of fluid the body retains is greater than the diuretic impact.
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The scientists found that amphetamine works with another ingredient, theophylline, a drug that is used for lung diseases such as asthma and bears a chemical resemblance to caffeine.
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The oil's fatty acids slow your body's absorption of caffeine, which helps extend your buzz.
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Kraft Heinz has introduced a line of Heinz barbecue sauces, a millennial-friendly MAX line of Maxwell House coffees with three caffeine calibrations, and Philadelphia Cheesecake Cups.
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Piper tells me the most likely causes of eye twitching are fatigue, stress, and consuming too much caffeine.
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This scalp treatment contains peptides, proteins, and caffeine.
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
play
noun
Definition 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
play
noun
caf·feine
\
ka-ˈfēn
,
ˈka-ˌfēn
\
Definition 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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