Simple Definition of warn
: to tell (someone) about possible danger or trouble
: to tell (someone) to do or not to do something in order to avoid danger or trouble
Examples of warn
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.
Origin of warn
Middle English, from Old English warnian; akin to Old High German warnōn to take heed, Old English wær careful, aware — more at wary
First Known Use: before 12th century
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