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caffeine

[ ka-feen, kaf-een, kaf-ee-in ]
/ kæˈfin, ˈkæf in, ˈkæf i ɪn /
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noun
Chemistry, Pharmacology. a white, crystalline, bitter alkaloid, C8H10N4O2, usually derived from coffee or tea: used in medicine chiefly as a nervous system stimulant.
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.

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Rarely caf·fein .

Origin of caffeine

First recorded in 1820–30; from French caféine, equivalent to café coffee + -ine -ine2

OTHER WORDS FROM caffeine

caf·fein·ic [ka-fee-nik, kaf-ee-in-ik], /kæˈfi nɪk, ˌkæf iˈɪn ɪk/, adjectivenon·caf·feine, nounnon·caf·fein·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

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British Dictionary definitions for caffeine

caffeine

caffein

/ (ˈkæfiːn, ˈkæfɪˌiːn) /

noun
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 2See also xanthine (def. 2)

Word Origin for caffeine

C19: from German Kaffein, from Kaffee coffee
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for caffeine

caffeine
[ kă-fēn ]

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: C8H10N4O2.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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