Definition
caffein
noun
- a bitter alkaloid compound found in coffee, tea, and other plants, used as a stimulant to increase alertness and reduce fatigue
Usage: Also spelled 'caffeine' (more common in modern usage); Uncountable noun
Examples
- Coffee contains a high amount of caffein that helps people stay awake.
- She avoids caffein in the evening because it keeps her from sleeping.
- Tea has less caffein than coffee.
- The energy drink is loaded with caffein and sugar.
- Caffein is a natural stimulant found in many plants.