warn

1. To make (someone) aware of (something impending); especially:
2. To make (someone) aware of (something impending); especially:
3. To make (someone) aware of (something impending); especially:
4. (obsolete) To make (someone) aware of (something impending); especially:
5. To caution or admonish (someone) against unwise or unacceptable behaviour.
6. To advise or order to go or stay away.
7. To give warning.