# caffeine

> English word · Noun · IPA /ˈkæfiːn/ · frequency rank #11,661

## Definitions
1. An alkaloid, C₈H₁₀N₄O₂, found naturally in tea and coffee plants, which acts as a mild stimulant on the central nervous system.

## Etymology
Borrowed from French caféine, from café (“coffee”), or German Caffein, Kaffein (cp. Coffein, Koffein), from Kaffee (“coffee”) (cp. Kaffe, Koffee, Koffe), or Italian caffè (“coffee”) + -ine.

## Common misspellings (9)
`acffeine`, `cafefine`, `cafeine`, `caffeien`, `caffeinne`, `caffenie`, `caffiene`, `ccaffeine`, `cfafeine`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/caffeine