caffeine

Rarely caf·fein

[ka-feen, kaf-een, kaf-ee-in]

noun

1. 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.

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.

caffeine

/ 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

caffeine

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: C ₈ H ₁₀ N ₄ O ₂ .

Other Word Forms

• caffeinic adjective
• noncaffeine noun
• noncaffeinic adjective

Word History and Origins

Origin of caffeine¹

First recorded in 1820–30; from French caféine, equivalent to café coffee + -ine -ine ²

Word History and Origins

Origin of caffeine¹

C19: from German Kaffein, from Kaffee _coffee

Example Sentences

Some popular drinks contain more caffeine than two cups of coffee.

From BBC

Traditionally, matcha is considered to contain antioxidants and have a more tempered caffeine effect than the "high" and "crash" of regular coffee but there is some debate over any proven health benefits.

From BBC

But he didn’t dispense caffeine pills to participants as Michaels did.

From Salon

Usually I’m going down there because I have a couple other caffeine crackheads in my social group and we go there.

From Los Angeles Times

A growing number of US teenagers are using caffeine pouches to get an energy rush, say experts who worry the trend could soon take off in the UK.

From BBC

Related Words

• cappuccino 
• espresso