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caffeine Line breaks: caf|feine
Pronunciation: /ˈkafiːn/

Definition of caffeine in English:


[mass noun]
An alkaloid compound which is found especially in tea and coffee plants and is a stimulant of the central nervous system.
Example sentences
  • The stimulant effects of caffeine in coffee are well known to help improve energy and alertness.
  • They have a similar effect to tea or coffee, since they contain the same alkaloid, caffeine.
  • In flowering plant pollen tubes, caffeine disrupts vesicle zonation at the tip and stops elongation.


Mid 19th century: from French caféine, from café 'coffee'.

Words that rhyme with caffeine

Delphine • Josephine

Definition of caffeine in:

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Word of the day innocuous
Pronunciation: ɪˈnɒkjʊəs
not harmful or offensive