noun

caffeine

KA-feen

noun

A natural stimulant found in coffee, tea, and cacao that increases alertness and reduces tiredness.

"Too much caffeine late in the day kept her awake all night."

"He switched to decaf to cut down on caffeine."

How to Use Caffeine

Learner’s notes

In plain EnglishThe stimulant in coffee and tea that keeps you alert and awake.

Common pairings

caffeine intake caffeine withdrawal high in caffeine

caffeines plural

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Too much _____ late in the day kept her awake all night.

Borrowed from French caféine, itself built from café ("coffee") plus the chemical suffix "-ine."

nine mine wine line sine dine fine vine pine tine Eine thine