caffeine

noun caf·feine \ ka-ˈfēn , ˈka-ˌ \

|Updated on: 17 Jun 2018

Definition of caffeine

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

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Examples of caffeine in a Sentence

Her doctor told her to avoid caffeine.

Recent Examples of caffeine from the Web

The Food and Drug Administration says caffeine in doses up to 400 mg (usually about five cups of coffee) is generally safe.

— fiza pirani, ajc, "What is Death Wish Coffee? ‘World’s strongest coffee’ soaring into space," 11 June 2018
Today, Starbucks, a company known for making mornings a little bit easier by providing caffeine fixes aplenty, implemented a price increase that's probably not significant enough to ruin customers' days but could give them a grumpier start.

— olivia harrison, refinery29.com, "Starbucks Increased Its Coffee Prices — Here's How Much More You'll Be Spending," 7 June 2018
Drinks: Get your caffeine fix with Bucky Done Woke, a blend of Nitro cold brew coffee, Campari, sweet vermouth and orange peel, or chill out with a plum brandy mimosa (both $10).

— samantha nelson, RedEye Chicago, "14 new brunches to brighten your Chicago summer," 31 May 2018
Cleveland diners know just where to satisfy their burger cravings, and Conroe readers shared their favorite spot for a caffeine fix.

— dana burke, Houston Chronicle, "Best-kept secrets of Houston's suburbs," 31 May 2018
Mhay was one of millions of customers who couldn’t get their caffeine fix Tuesday afternoon.

— joshua fechter, San Antonio Express-News, "Starbucks grapples with racial bias as it closes 8,000 U.S. stores for training," 29 May 2018
While hitting your local coffee house may seem convenient, spending this much to get your caffeine fix just isn't practical.

— The Motley Fool, "Boost your income: 27 things you're probably wasting your money on right now," 4 May 2018
With numerous independent chains and a growing number of individual coffee shops, the city has never been a better place for a caffeine fix.

— allison steele, Philly.com, "Protesting Starbucks? Here are Philly's best independent coffee shops," 16 Apr. 2018
Other practical considerations Layish recommends for better sleep include avoiding caffeine after 2 p.m. and limiting it in the hours prior, avoiding alcohol near bedtime, and exercising during the day -- at least two hours before bed.

— katie parsons, OrlandoSentinel.com, "Americans aren't sleeping enough, but early risers might live longer," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'caffeine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.