/ wɔːn; NAmE wɔːrn/ verb
1.
warn (sb) (of sth) | warn (sb) (about / against sb/sth) to tell sb about sth, especially sth dangerous or unpleasant that is likely to happen, so that they can avoid it :
[ vn ]
I tried to warn him, but he wouldn't listen.
If you're thinking of getting a dog, be warned —they take a lot of time and money.
He warned us against pickpockets.
[ vn that ]
She was warned that if she did it again she would lose her job.
[ vn wh- ]
I had been warned what to expect.
[ v ]
Police have warned of possible delays.
[also v that , also v speech , vn speech ]
2.
warn (sb) (against / about sth) to strongly advise sb to do or not to do sth in order to avoid danger or punishment
SYN advise :
[ v ]
The guidebook warns against walking alone at night.
[ vn to inf ]
He warned Billy to keep away from his daughter.
[also vn ]
3.
[ vn ] ( in sport, etc. ) to give sb an official warning after they have broken a rule :
The referee warned him for dangerous play.
•
PHRASAL VERBS
- warn sb off (sth)
••
WORD ORIGIN
Old English war(e)nian , wearnian , from a West Germanic base meaning be cautious .