warn about

warn someone about someone or something

to advise someone about the dangers associated with someone or something. Didn't I warn you about the dangers of going there? I warned you about Alice.
See also: warn

warn about

v.
1. To make someone aware of the actual or potential harm, danger, or evil associated with something: I warned the kids about riding their bikes in the street.
2. To make aware in advance of some actual or potential harm, danger, or evil: The report warned about a possible attack.
See also: warn
References in periodicals archive ?
Early warning is obviously more focused on strategic than on tactical warning and, if as envisaged, will also in future warn about for instance potential terror attacks on African countries and will have to increasingly rely on warning intelligence.
They argued that the distillers had failed to warn about the dangers of drinking during pregnancy.