Pronunciation: (wôr'ning),[key] —n. 1. the act or utterance of one who warns or the existence, appearance, sound, etc., of a thing that warns.
2. something that serves to warn, give notice, or caution: We fired a warning at the intruders. 3. Meteorol.an announcement from the U.S. National Weather Service alerting the public that a storm or other weather-related hazard is imminent and that immediate steps should be taken to protect lives and property. Cf. advisory (def. 5), storm warning (def. 2), watch (def. 23).
—adj. serving to warn, advise, caution: a warning bell.