Definition of warn in English:


Pronunciation /wôrn/ /wɔrn/

Translate warn into Spanish


reporting verb
  • 1Inform someone in advance of an impending or possible danger, problem, or other unpleasant situation.

    with object ‘his father had warned him of what might happen’
    • ‘“He's going to humiliate you,” John warned’
    • ‘the union warned that its members were close to going on strike’
    • ‘The report also warned of the dangers of failing to improve the lot of ordinary Iraqis.’
    • ‘It was a habit left over from the old days when the king and his ministers were thus warned of danger.’
    • ‘Because of the possible dangers we are warning customers not to use them.’
    • ‘It also warns of the dangers of transferring patients when beds are not available.’
    • ‘We in the Newtown and Guillamene Swimming Club are constantly warning about the dangers but at the end of the day it's up to parents to ensure the safety of their children.’
    • ‘They become one-way routes, but they don't move, because people were not given the kind of advance warning they should get.’
    • ‘He also warned about the dangers of being divided by the scapegoating of refugees.’
    • ‘It has since emerged that she had been warned of the rumours at least two days before.’
    • ‘The Bank of England is poised to warn of the dangers of a collapse in house prices.’
    • ‘Was that old woman she met earlier telling the truth, and that she really was warning Alli of a possible danger that could befall her?’
    • ‘Hector said to his men warning them of the possible dangers of an ambush.’
    • ‘Parents also should be informed about the dangers and warning signs of inhalant abuse.’
    • ‘Mary, on her way to Greenwich, was warned of the trap and rode pell-mell for Norfolk.’
    • ‘The conclusion also warns that I might possibly be frustrated if I don't have an outlet for my creative urges.’
    • ‘They're warning of a heightened possibility of an eruption after more than a thousand small earthquakes.’
    • ‘The residents' acute fear of crime is itself a source of real danger, warns Budapest fire chief Peter Bende.’
    • ‘Mr Sheard warns us of the dangers of Airedale and other local hospitals being incorporated into Bradford.’
    • ‘‘It was a nice sunny day, but unfortunately there were no signs, no flags warning us about the dangers,’ he said.’
    • ‘Bulky agricultural machinery which dominates country roads should be accompanied by advance warning vehicles, a coroner said.’
    • ‘He was told that advance warning signs were put in place and that, if he could obtain permission from landowners, the council would remove some trees.’
    notify, alert, apprise, give notice, inform, tell, let someone know, make someone aware, give a warning to, give fair warning to, forewarn, put someone on guard, put someone on notice, remind
    View synonyms
    1. 1.1Give (someone) forceful or cautionary advice about their actions or conduct.
      ‘friends warned her against the marriage’
      • ‘they warned people not to keep large amounts of cash in their homes’
      • ‘they warned against false optimism’
      • ‘Police are warning drivers to remain cautious today after a winter storm dumped as much as 14 inches of snow on parts of eastern Virginia.’
      • ‘Whatever the reason, Shuggy's behaviour eventually prompted a police caution, warning him that if he didn't calm down then he would be in serious trouble.’
      • ‘Police are warning the public to be cautious when opening their door to strangers.’
      • ‘Well, we have for a long time provided early warning advice on the launch of ballistic missiles.’
      • ‘The four were sent a letter from the council formally warning them about their conduct on January 20.’
      • ‘Despite officers warning him about his conduct he continued to hurl insults and was arrested.’
      • ‘Now police are warning anyone who used the machine over the Easter weekend, including the bank holiday Monday, to check their bank accounts in case they too have become victims of the scam.’
      • ‘Police are warning farmers, horse owners and equestrian establishments to check security and be extra vigilant following a number of thefts in the North Wiltshire area.’
      • ‘Police are warning residents not to confront a gang of brazen and aggressive thieves who have struck more than 50 times in Wiltshire, stealing power tools from vans.’
      • ‘More than 20 other people were sent letters from housing officials and police officers warning them that their behaviour could constitute a public nuisance.’
      • ‘Police are warning people to be on their guard against credit card cheats after a Braintree woman had hers stolen and the thief tried to trick her into revealing her secret identity number.’
      • ‘Police are warning motorists to expect severe problems with road closures, especially on Friday, and advising people to make other arrangements.’
      • ‘Police are warning farmers to secure valuable machinery and to mark it for identification, as well as maintaining serial number records.’
      • ‘A huge pop concert for girl guides, a demonstration, and two major sporting events all take place on Saturday, and police are warning drivers to stay clear.’
      • ‘Police are warning troublemakers that their behaviour will not be tolerated following another weekend of assaults and vandalism.’
      • ‘Police officers are also warning elderly people to be on their guard tonight because Halloween can be rife with people committing distraction burglaries.’
      • ‘Then suddenly and without warning the police moved in on horseback and foot, wrestling random fans to the floor and using their batons with sickening accuracy.’
      • ‘Police are warning elderly people to be on their guard after a Balham resident was duped out of £10, believing he was helping a neighbour.’
      • ‘Police are warning people to make sure their houses are secure even when they are in them following a spate of ‘creeper’ burglaries.’
      advise, exhort, urge, counsel, caution
      View synonyms


    warn someone off the course
    British Horse Racing
    • Prohibit someone who has broken the laws of the Jockey Club from riding or running horses at meetings under the Jockey Club's jurisdiction.

Phrasal Verbs

    warn off
    • warn someone offOrder someone to keep away from somewhere or refrain from doing or consuming something.

      ‘Darren had very effectively warned them off’
      • ‘he has been warned off booze’


Old English war(e)nian, wearnian, from a West Germanic base meaning ‘be cautious’; compare with ware.