[ wawrn ]
See synonyms for: warnwarnedwarningwarns on Thesaurus.com

verb (used with object)
  1. to give notice, advice, or intimation to (a person, group, etc.) of danger, impending evil, possible harm, or anything else unfavorable: They warned him of a plot against him. She was warned that her life was in danger.

  2. to urge or advise to be careful; caution: to warn a careless driver.

  1. to admonish or exhort, as to action or conduct: She warned her employees to be on time.

  2. to notify, advise, or inform: to warn a person of an intended visit.

  3. to give notice to (a person, group, etc.) to go, keep at a distance, etc. (often followed by away, off, etc.): A sign warns trespassers off the grounds. A marker warned boats away from the dock.

  4. to give authoritative or formal notice to (someone); order; summon: to warn a person to appear in court.

verb (used without object)
  1. to give a warning; caution: to warn of further disasters.

Origin of warn

before 1000; Middle English warnen,Old English warnian; cognate with German warnen.Cf. ware2

synonym study For warn

Warn, caution, admonish imply attempting to prevent another from running into danger or getting into unpleasant or undesirable circumstances. To warn is to speak plainly and usually in strong terms: to warn him about danger and possible penalties. To caution is to advise about necessary precautions, to put one on one's guard about possibly harmful circumstances or conditions, thus emphasizing avoidance of undesirable consequences: to caution him against driving in such weather. Admonish suggests giving earnest, authoritative advice with only tacit references to danger or penalty: to admonish a person for neglecting his duties.

Other words for warn

Other words from warn

  • warner, noun
  • pre·warn, verb (used with object)
  • re·warn, verb (used with object)
  • un·warned, adjective
  • well-warned, adjective

Words Nearby warn

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use warn in a sentence

British Dictionary definitions for warn


/ (wɔːn) /

  1. to notify or make (someone) aware of danger, harm, etc

  2. (tr; often takes a negative and an infinitive) to advise or admonish (someone) as to action, conduct, etc: I warn you not to do that again

  1. (takes a clause as object or an infinitive) to inform (someone) in advance: he warned them that he would arrive late

  2. (tr; usually foll by away, off, etc) to give notice to go away, be off, etc: he warned the trespassers off his ground

Origin of warn

Old English wearnian; related to Old High German warnēn, Old Norse varna to refuse

Derived forms of warn

  • warner, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012