Main Entry:

caf·feine

Pronunciation:

\ka-ˈfēn, ˈka-ˌ\

Function:

noun

Etymology:

German Kaffein, from Kaffee coffee, from French café

Date:

circa 1823

: a bitter alkaloid C₈H₁₀N₄O₂ found especially in coffee, tea, cacao, and kola nuts and used medicinally as a stimulant and diuretic