The action of the verb warn; an instance of warning someone.
Something spoken or written that is intended to warn.
To make (someone) aware of (something impending); especially:
To caution or admonish (someone) against unwise or unacceptable behaviour.
(chiefly with "off", "away", and similar words) To advise or order to go or stay away.
To give warning.
Used to warn of danger in signs and notices.