warned; warning; warns
Synonyms of warnnext

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
warner noun

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 on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The outbreaks have mostly affected children and have come as infectious disease experts warn that rising public distrust of vaccines generally may be contributing to the spread of a disease once declared eradicated by public health officials. Arkansas Online, 9 Feb. 2026 But then again, you readers did try to warn me. Sean McIndoe, New York Times, 9 Feb. 2026 The firm ran ads warning of the dangers of marijuana during the weeks leading up to the vote on the Amendment 3, which won approval from 56% of Florida voters but failed to reach the 60% threshold needed to become law. Jeffrey Schweers, The Orlando Sentinel, 8 Feb. 2026 The outbreaks have mostly impacted children and have come as infectious disease experts warn that rising public distrust of vaccines generally may be contributing to the spread of a disease once declared eradicated by public health officials. Matt Brown, Denver Post, 8 Feb. 2026 See All Example Sentences for warn

Word History

Etymology

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 ware entry 1

First Known Use

before the 12th century, in the meaning defined at transitive sense 1a

Time Traveler
The first known use of warn was before the 12th century

Browse Nearby Words

Cite this Entry

“Warn.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/warn. Accessed 10 Feb. 2026.

Kids Definition

warn

verb
1
a
: to give notice to beforehand especially of danger or evil
b
: to give advice to : counsel
2
: to order to go or stay away
warned us off their land
warner noun

More from Merriam-Webster on warn

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster