warn

verb \ ˈwȯrn \

Updated on: 11 Sep 2017

Definition of warn

transitive verb

1 a :to give notice to beforehand especially of danger or evil

b :to give admonishing advice to :counsel

c :to call to one's attention :inform

2 :to order to go or stay away —often used with off

intransitive verb

:to give a warning

—

warner

noun

See warn defined for English-language learners

See warn defined for kids

Examples of warn in a Sentence

I had been warned about the difficulties of the job.
She warned me that the stove was still hot.
“This won't be easy,” he warned.
Nobody warned me about the dangers.
I warned him to be careful, but he didn't listen to me.
She warned us not to go too close to the fire.

Recent Examples of warn from the Web

Erickson warns that some coastal rivers won’t be able to drain effectively because Harvey’s winds are pushing in storm surge, aggravating flooding in areas already drenched by more than 20 inches (51 centimeters) of rain.

— Washington Post, "Western Louisiana in crosshairs as Harvey moves back to land," 30 Aug. 2017
The document, directed at both Britain and the EU, warned that firms are considering moving their European headquarters out of the U.K. and said a long period of uncertainty would be damaging.

— alex morales, Bloomberg.com, "Theresa May Has Her Eye on a Glittering Trade Prize," 29 Aug. 2017
And as Mr. Trump prepares to outline his corporate tax overhaul ideas in a speech on Wednesday in Springfield, Mo., economists and tax experts warn that the path is likely to be treacherous.

— patricia cohen, New York Times, "Trump Tax Plan May Free Up Corporate Dollars, but Then What?," 29 Aug. 2017
Indians in other places also took action: villagers at Otsinigo, New York, warned liquor dealers to stay away; some Iroquois chiefs banned the sale of rum in their communities as well.

— Longreads, "America’s First Addiction Epidemic," 29 Aug. 2017
Heavy rain from a tropical wave lingering over South Florida is triggering a flood warning through Saturday.

— jenny staletovich, miamiherald, "South Florida flood warning to last through Saturday," 24 Aug. 2017
The World Health Organization (WHO) warned that 35 to 77 million people in Bangladesh could be at risk of drinking water with unsafe levels of arsenic.

— giorgia guglielmi, Science | AAAS, "Arsenic in drinking water threatens up to 60 million in Pakistan," 23 Aug. 2017
In the days leading up to the totality, medical professionals, retailers and past victims warned of the dangers of looking directly at the eclipse without any eye protection.

— lindsey murray, Good Housekeeping, "This Test Could Tell You If You Damaged Your Sight During the Eclipse," 23 Aug. 2017
The McHenry County Department of Health warns residents to take precautions until the first hard frost.

— grace wong, McHenry County, "McHenry County reports first West Nile virus case of year," 23 Aug. 2017

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

Origin and Etymology of warn

Middle English warnen, going back to Old English wearnian, warnian "to be on one's guard, make aware, put on one's guard," going back to West Germanic *warnōjan- (whence Middle Dutch waernen "to provide with, give notice of a danger," Old High German warnōn), probably causative derivative of Germanic *wara- "cognizant, watchful" — more at ¹ware

NEW! Time Traveler

First Known Use: before 12th century

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