forewarn

The story

1. Proto-Germanic · inherited from*furawarnōną“to forewarn”
2. Old English · inherited fromforewarnian“to take warning beforehand; forewarn”
3. Middle English · inherited from*forewarnen
4. English todayforewarn

Early 14th century, from Middle English *forewarnen (suggested by Middle English forewarned, forewarning, forewarner, etc.), from Old English forewarnian (“to take warning beforehand; forewarn”), from Proto-Germanic *furawarnōną (“to forewarn”), equivalent to fore- + warn. Cognate with German vorwarnen (“to forewarn”), Swedish förvarna (“to forewarn”).