Definitions for caffeinekæˈfin, ˈkæf in

This page provides all possible meanings and translations of the word caffeine

Princeton's WordNet

  1. caffeine, caffein(noun)

    a bitter alkaloid found in coffee and tea that is responsible for their stimulating effects


  1. caffeine(Noun)

    An alkaloid, CHNO, found naturally in tea and coffee plants which acts as a mild stimulant of the central nervous system.

  2. Origin: From caféine, from café or Coffein, from Kaffee

Webster Dictionary

  1. Caffeine(noun)

    a white, bitter, crystallizable substance, obtained from coffee. It is identical with the alkaloid theine from tea leaves, and with guaranine from guarana

  2. Origin: [Cf. F. cafine. See Coffee.]


  1. Caffeine

    Caffeine is a bitter, white crystalline xanthine alkaloid that acts as a stimulant drug. Caffeine is found in varying quantities in the seeds, leaves, and fruit of some plants, where it acts as a natural pesticide that paralyzes and kills certain insects feeding on the plants, as well as enhancing the reward memory of pollinators. It is most commonly consumed by humans in infusions extracted from the seed of the coffee plant and the leaves of the tea bush, as well as from various foods and drinks containing products derived from the kola nut. Other sources include yerba maté, guarana berries, guayusa, and the yaupon holly. In humans, caffeine acts as a central nervous system stimulant, temporarily warding off drowsiness and restoring alertness. It is the world's most widely consumed psychoactive drug, but unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world. Beverages containing caffeine, such as coffee, tea, soft drinks, and energy drinks, enjoy great popularity. In North America, 90% of adults consume caffeine daily. Part of the reason caffeine is classified by the Food and Drug Administration as GRAS is that toxic doses are much higher than typically used doses. Ordinary consumption can have low health risks, even when carried on for years – there may be a modest protective effect against some diseases, including Parkinsons Disease, and certain types of cancer. Caffeine can have both positive and negative effects on anxiety disorders. Some people experience sleep disruption if they consume caffeine, especially during the evening hours, but others show little disturbance and the effect of caffeine on sleep is highly variable.

U.S. National Library of Medicine

  1. Caffeine

    A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.

Translations for caffeine

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