warn
/wɔːn
/verb [reporting verb]
1Inform someone in advance of a possible danger, problem, or other unpleasant situation: [with object]: his father had warned him of what might happen [with direct speech]: ‘He’s going to humiliate you,’ John warned [no object]: traffic signals warned of fog [with clause]: the union warned that its members were 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.
Synonyms
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 notice/guard, remind;
raise/sound the alarm
informal tip off, put wise
1.1 [with object] Give someone cautionary advice about their actions or conduct: he warned the chancellor against raising taxes [with object and infinitive]: police warned people not to keep large amounts of cash in their homes [no object]: 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.
Synonyms
advise, exhort, urge, counsel, caution;
put on the alert, put someone on guard
Phrases
warn someone off the course
Phrasal verbs
warn someone off
Derivatives
warner
- The helicopter's electronic warfare systems include a radar warning receiver, laser warning receiver, missile approach warner and chaff and flare dispensers.
- The laser warner provides broadband laser frequency coverage to detect and display rangefinding, designating and missile guidance laser threats.
- The defensive aids suite could include a radar warner, missile launch and approach warner, and chaff and flare decoy dispensers.
Origin
Old English war(e)nian, wearnian, from a West Germanic base meaning 'be cautious'; compare with ware2.