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caf·feine also caf·fein

(kă-fēn, kăfēn′)

A bitter white alkaloid, C₈H₁₀N₄O₂, found in certain plants such as cacao, coffee, kola, and tea, that stimulates the central nervous system and body metabolism and is used in medicine, usually in combination with other drugs, to relieve headaches and treat respiratory conditions in premature infants.

[German Kaffein (from Kaffee, coffee) or French caféine, both from French café, coffee; see CAFé.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

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Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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