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caffeine

[ka-feen, kaf-een, kaf-ee-in] / kæˈfin, ˈkæf in, ˈkæf i ɪn /


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Scientists found that consuming caffeine at night can increase impulsive behavior, raising the likelihood of risky or uncontrolled actions.

From Science Daily • Mar. 31, 2026

To test this, the team fed fruit flies caffeine under different conditions, including varying doses, daytime versus nighttime exposure, and combinations with sleep deprivation.

From Science Daily • Mar. 31, 2026

Both brands’ 12-ounce cans carry the same 200 milligrams of caffeine, too.

From The Wall Street Journal • Mar. 25, 2026

It was a group powered by caffeine, Johnston said, and their coffee came in handy when they needed a liquid prop to do quick demos with the prototypes to test their absorbency.

From The Wall Street Journal • Mar. 20, 2026

They were laying off sugar or carbs or caffeine or meat or dairy, but maybe a little butter was fine now and then.

From "We Are Okay" by Nina LaCour