warn

verb

ˈwȯrn How to pronounce warn (audio)
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

intransitive verb

: to give a warning
warner noun

Synonyms of warn

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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 Folsom Fire Department noted that signs posted on the bridge warn people not to jump from it. — Richard Ramos, CBS News, 6 Aug. 2026 And by lunch, the bloody tableau has been forgotten, right on time for the arrival of Robert Mallory, the new student Susan had warned the others about. — Louis Peitzman, Vulture, 6 Aug. 2026 Eight maritime groups signed a joint open letter to the UN and the International Maritime Organization (IMO) on Monday, warning that introducing tolls could drive up costs for consumers and undermine the principles of free navigation. — Todd Symons, CNN Money, 6 Aug. 2026 However, the law professor warned of agencies that use the label as a way of gaining trust with their surrounding communities without tangible effort to engage with all social groups. — Nollyanne Delacruz, Mercury News, 5 Aug. 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

Phrases Containing warn

Rhymes for warn

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Browse Nearby Words

warmwater
warn
warn't
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Cite this Entry

“Warn.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/warn. Accessed 6 Aug. 2026.

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Kids Definition

warn

verb
ˈwȯ(ə)rn How to pronounce warn (audio)
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

Nglish: Translation of warn for Spanish Speakers

Last Updated: - Updated example sentences
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