To make a remark or provide information when it is inappropriate or indiscreet to do so, or when one does not have permission or the authority to do so.
To notify or inform (someone, about something).
To caution or admonish (someone) against unwise or unacceptable behaviour.
To give warning.
To summon (someone) to or inform of a formal meeting or duty.
To advise or order to go or stay away.
To make (someone) aware of impending danger, evil, etc.