caffeine
Use Caffeine in a sentence
in, ˈkæf noun 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.
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Based on the Random House Dictionary, © Random House, Inc. 2013.
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Based on the Random House Dictionary, © Random House, Inc. 2013.
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Link To caffeine
00:10
Caffeine
is always a great word to know.
So is ort. Does it mean:
| a scrap or morsel of food left at a meal. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
Collins
World English Dictionary
caffeine or caffein (ˈkæfiːn, ˈkæfɪˌiːn, ˈkæfiːn, ˈkæfɪˌiːn) ![[Click for IPA pronunciation guide]](http://static.sfdict.com/dictstatic/g/d/dictionary_questionbutton_default.gif) | |
| —n | |
| See also xanthine a white crystalline bitter alkaloid responsible for the stimulant action of tea, coffee, and cocoa: a constituent of many tonics and analgesics. Formula: C8H10N4O2 | |
| [C19: from German Kaffein, from Kaffee | |
| caffein or caffein | |
| —n | |
| [C19: from German Kaffein, from Kaffee | |
Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
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2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
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Etymonline
Word Origin & History
caffeine
1830, from Ger. Kaffein, coined by chemist F.F. Runge (1795-1867), apparently from Ger. Kaffee "coffee" + chemical suffix -ine (Ger. -in). The form of the English word may be via Fr. caféine.
Online Etymology Dictionary, © 2010 Douglas Harper
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American Heritage
Medical Dictionary
caffeine caf·feine or caf·fein (kā-fēn', kāf'ēn', kāf'ē-ĭn)
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.
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Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
| caffeine (kā-fēn') Pronunciation Key
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 © 2002. Published by Houghton Mifflin. All rights reserved.
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Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Example sentences
Or maybe it's simply the fact we've had too much caffeine and too little sleep.
Too much caffeine equals lack of focus, as well as a sugar crash.
The caffeine-reduced extract can then be reused to begin the process anew.
Alkaloids, which include caffeine and nicotine, are a highly diverse group of chemicals with many unusual properties.
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