caffeine

[ ka-feen, kaf-een, kaf-ee-in ]

noun

1. Chemistry, Pharmacology. a white, crystalline, bitter alkaloid, C 8 H 10 N 4 O 2 , usually derived from coffee or tea: used in medicine chiefly as a nervous system stimulant.
2. Informal. a drink, usually coffee or tea, containing this stimulant:

   We sipped our caffeine on the balcony with its views of sea stacks, rocky coves, and the ever-changing ocean.

caffeine

/ ˈkæfɪˌiːn; ˈkæfiːn /

noun

1. See xanthine
   a white crystalline bitter alkaloid responsible for the stimulant action of tea, coffee, and cocoa: a constituent of many tonics and analgesics. Formula: C 8 H 10 N 4 O 2 See also xanthine

caffeine

/ kă-fēn′ /

1. A bitter white alkaloid found in tea leaves, coffee beans, and various other plant parts. It is a mild stimulant. Caffeine is a xanthine and similar in structure to theobromine and theophylline. Chemical formula: C 8 H 10 N 4 O 2 .

Other Words From

• caf·fein·ic [ka-, fee, -nik, kaf-ee-, in, -ik], adjective
• non·caf·feine noun
• non·caf·fein·ic adjective

Word History and Origins

Origin of caffeine¹

First recorded in 1820–30; from French caféine, equivalent to café coffee + -ine -ine ²

Word History and Origins

Origin of caffeine¹

C19: from German Kaffein, from Kaffee coffee

Example Sentences

Now its lattes and caffeine are flying through the sky in silent drones moving at 80 miles per hour.

From Fortune

Of Nuun Sport’s 13 flavors, I highly recommend citrus fruit, strawberry lemonade, and cherry limeade plus caffeine.

From Outside Online

I love drinking tea, but I have to cut off my caffeine intake pretty early in the day if I want to get to sleep at a decent hour.

From Popular-Science

“If you want to understand penicillin or caffeine, you can’t do that on a conventional supercomputer, no matter how big you make it,” Krishna explained.

From Fortune

Nestlé Chief Executive Officer Mark Schneider skips his afternoon Nespresso, as genetic tests revealed his body processes caffeine only slowly, depriving him of sleep.

From Fortune

The Pentagon security reviewers must have been suffering a dearth of caffeine or sleep.

From The Daily Beast

The story gets out that Obama skipped his usual afternoon dose of caffeine heading toward the U.N. meeting.

From The Daily Beast

This clean source of caffeine is the next noble, and healthy, substitute for your daily cup of coffee.

From The Daily Beast

A “caffeine nap,” or a quick cup of something caffeinated followed by a nap, outperforms both a nap or caffeine independently.

From The Daily Beast

Einöther authored the most comprehensive review of research on caffeine to date.

From The Daily Beast

Both contain stimulating alkaloids, theobromine and caffeine, and fat is a notable constituent of cocoa.

From Project Gutenberg

It's thick enough to stand a spoon up in, and it has way more caffeine than the kiddee-pops like Red Bull.

From Project Gutenberg

I'd totaled about three hours of sleep, and even three cups of the Turk's caffeine mud failed to jump-start my brain.

From Project Gutenberg

It appears to be identical with caffeine, the active principle of coffee and tea.

From Project Gutenberg

This first term gives rise to a series of bodies in lateral groups, of which the most interesting are caffeine and theobromine.

From Project Gutenberg

Related Words

• cappuccino
• espresso