Définitions
1.VerbTo make (someone) aware of (something impending); especially:
To make (someone) aware of impending danger, evil, etc. .mw-parser-output .defdate{font-size:smaller}"We waved a flag to warn the oncoming traffic about the accident.; I phoned to warn him of the road closure.; I warned him he'd be getting a huge box of birthday presents from me.; The sheriff warned her to appear in court."
2.VerbTo make (someone) aware of impending danger, evil, etc. .mw-parser-output .defdate{font-size:smaller}"We waved a flag to warn the oncoming traffic about the accident.; I phoned to warn him of the road closure."
3.VerbTo notify or inform (someone, about something)."I warned him he'd be getting a huge box of birthday presents from me."
4.VerbTo summon (someone) to or inform of a formal meeting or duty."The sheriff warned her to appear in court."
5.VerbTo make a sound (e.g. clicking or whirring) indicating that it is about to strike or chime (an hour).
6.VerbTo caution or admonish (someone) against unwise or unacceptable behaviour."He was warned against crossing the railway tracks at night.; Don't let me catch you running in the corridor again, I warn you."
7.VerbTo advise or order to go or stay away."A sign warns trespassers off/away from the site."
8.VerbTo give warning.