1. inform someone in advance of an impending or possible danger, problem, or other unpleasant situation: "his father had warned him of what might happen"Similarnotifyalertapprisegive noticeinformtelllet someone knowmake someone awaregive a warning togive fair warning toforewarnput someone on notice/guardremindraise/sound the alarminformal:tip offput wise
▪ give (someone) forceful or cautionary advice about their actions or conduct:"friends warned her against the marriage"Similaradviseexhorturgecounselcautionput on the alertput someone on guard
Word OriginOld Englishwar(e)nian, wearnian, from a West Germanic base meaning ‘be cautious’; compare with ware2.
