caffeine
or caf·fein
[ ka-feen, kaf-een, kaf-ee-in ]
/ kæˈfin, ˈkæf in, ˈkæf i ɪn /
noun Chemistry, Pharmacology.
a white, crystalline, bitter alkaloid, C8H10N4O2, usually derived from coffee or tea: used in medicine chiefly as a nervous system stimulant.
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Nearby words
cafeteria-style, cafetiere, cafetorium, caff, caffeinated, caffeine, caffeinic, caffeinism, caffey's disease, caffey's syndrome, caffè latte
Related formscaf·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. 2019
Examples from the Web for caffeine
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
Word Origin and History for caffeine
caffeine
trimethyl-derivative of xanthine, 1830, from German Kaffein, coined by chemist F.F. Runge (1795-1867), apparently from German Kaffee "coffee" (see coffee) + chemical suffix -ine (2) (German -in). The form of the English word may be via French caféine.
Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for caffeine
caffeine
n.
A bitter white alkaloid often derived from tea or coffee and used chiefly as a mild stimulant and in the treatment of certain kinds of headache.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science 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.