1
general::
warn
to tell someone about something bad or dangerous that might happen, so that they can avoid it or prevent it:
• I warned you about sitting out in the sun too long. • We were warned that there could be delays on the motorway, so we took another route.
give somebody a warning
to tell someone that if they continue to behave in an unsatisfactory way, they will be punished:
• He’s already been given several warnings about handing in his essays late. • The US gave a warning that if the hostages were not released, it would be forced to take military action.
alert
to officially or publicly warn people of possible danger so that they can prevent it or be ready to deal with it:
• a campaign to alert people to the dangers of smoking • An anonymous caller alerted the police that a bomb was due to go off.
tip somebody off
informal to secretly warn someone about something that is going to happen – used especially about warning the police about a crime:
• The police found the drugs after being tipped off by local residents. • Informants tipped the FBI off.
caution
formal to warn someone to do or not to do something in order to avoid a dangerous or bad result:
• People are being cautioned against using credit cards abroad, in case of fraud. • Health officials have cautioned the public to wash fruit thoroughly before eating it.
forewarn
[ usually passive ] formal to warn someone about something that is going to happen, so that you are expecting it or ready for it:
• We had been forewarned that the roads weren’t very good.
Longman-Thesaurus
2
general::
verb ADV. firmly | clearly | bluntly The chancellor bluntly warned the Cabinet to axe public spending or face higher taxes. | sternly | softly ‘Don't, ’ he warned softly. | specifically We were specifically warned against buying the house. | duly Having been duly warned that I would get nowhere with my application, I went right ahead and applied anyway. | constantly, repeatedly My mother constantly warned me not to go into teaching. | publicly VERB + WARN had better, have to, must, should I must warn you that some of these animals are extremely dangerous. I thought I should warn her about it. | try to I did try to warn you. | fail to She claimed doctors had failed to warn her of the risks involved. PREP. about No one had warned us about the unbearable heat. | against We were warned against drinking the local water. | of The report warns of the dangers of smoking. They warned us of the risks involved. PHRASES be warned You will get better?but be warned, it may be a long process.
Oxford Collocations Dictionary