Definitions

caffeine

[ka-feen, kaf-een, kaf-ee-in] / kæˈfin, ˈkæf in, ˈkæf i ɪn /

NOUN

coffee

Synonyms

STRONGEST

cappuccino espresso

STRONG

brew decaf decoction demitasse ink java mocha mud perk

WEAK

battery acid café café au lait café noir forty weight hot stuff jamocha joe varnish remover

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

caffeine

This suggests that caffeine is probably not the only substance responsible for the association.

From Science Daily ● Jul. 25, 2026

Research on the benefits and risks of caffeine consumption has been mixed.

From The Wall Street Journal ● Jul. 25, 2026

Scientists do not yet know whether caffeine is responsible for that association.

From Science Daily ● Jul. 22, 2026

Coffee is not the only source of caffeine.

From Science Daily ● Jul. 22, 2026

We all knew the effect caffeine had on Ms. Gruwell.

From "The Freedom Writers Diary" by The Freedom Writers