warn

verb

ˈwȯrn 

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

intransitive verb

: to give a warning

warner noun

Synonyms

• alert
• advise

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

Last month state immigration advocates warned that arrests of undocumented immigrants were ramping up in the state, creating anxiety and fear in communities with people taken every day. —Livi Stanford, Hartford Courant, 14 July 2025

The National Weather Service discussion on Monday morning warned that extreme heat conditions would continue in the region as a high-pressure center lingers. —Marshall Shepherd, Forbes.com, 14 July 2025

The report warned that the influx of more affordable Chinese goods would create greater challenges for local businesses in the region and impact their economies. —Mayu Saini, Sourcing Journal, 14 July 2025

Life-threatening flooding was possible in western Union County, New Jersey, the National Weather Service warned. —ABC News, 14 July 2025

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

Phrases Containing warn

• I have to warn you
• pre-warn
• warn off

Rhymes for warn

• borne
• bourn
• bourne
• corn
• morn
• mourn
• porn
• scorn
• shorn
• sworn
• thorn
• torn

Kids Definition

warn

verb

ˈwȯ(ə)rn 

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