An Etymological Dictionary of the German Language/Annotated/Jungfer
Modern High German Jungfer, feminine, ‘young girl, virgin, maid, maiden,’ is developed from Middle High German juncwrouwe, ‘noble maiden, young lady’ (thus, even in Middle High German, ver appears for the unaccented proclitic Frau). To this is allied Junker, masculine, ‘young nobleman, squire’ (properly ‘son of a duke or count’), from Middle High German junc-hē̆rre, ‘young lord, noble youth’; corresponding to Dutch jonker, jonkheer, whence English younker is borrowed.