caffeine

[ ka-feen, kaf-een, kaf-ee-in ]
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noun
  1. Chemistry, Pharmacology. a white, crystalline, bitter alkaloid, C8H10N4O2, 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.

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Origin of caffeine

1
First recorded in 1820–30; from French caféine, equivalent to café coffee + -ine -ine2
  • Rarely caf·fein .

Other words from caffeine

  • caf·fein·ic [ka-fee-nik, kaf-ee-in-ik], /kæˈfi nɪk, ˌkæf iˈɪn ɪk/, adjective
  • non·caf·feine, noun
  • non·caf·fein·ic, adjective

Words Nearby caffeine

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

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British Dictionary definitions for caffeine

caffeine

caffein

/ (ˈkæfiːn, ˈkæfɪˌiːn) /


noun
  1. 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 (def. 2)

Origin of caffeine

1
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 ]


  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: C8H10N4O2.

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