Main Entry: warn

Pronunciation: \ˈwȯrn\

Function: verb

Etymology: Middle English, from Old English warnian; akin to Old High German warnōn to take heed, Old English wær careful, aware — more at wary

Date: before 12th century

transitive verb 1 a : to give notice to beforehand especially of danger or evil b : to give admonishing advice to : counsel c : to call to one's attention : inform
2 : to order to go or stay away —often used with offintransitive verb : to give a warning

— warn·er noun