warned; warning; warns

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 International Atomic Energy Agency has previously warned that bombing active enrichment sites, particularly Fordow, could pose environmental and health risks. Brian Bennett, Time, 22 June 2025 Experts say the end of the Islamic Republic is no longer unthinkable — but warn that what replaces it could either lift the country toward a freer future or plunge it into instability. Efrat Lachter , Caitlin McFall, FOXNews.com, 21 June 2025 However, opponents warned the most vulnerable in society, such as disabled and older people, could be at risk of being coerced directly or indirectly into ending their lives to save money or relieve the burden on family members. Arkansas Online, 21 June 2025 The war between Israel and Iran began its ninth day Saturday as the two countries continued to trade missile attacks, and Iran's foreign minister warned against the U.S. getting actively involved. Kate Bartlett, NPR, 21 June 2025 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 26 Jun. 2025.

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

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