An Etymological Dictionary of the German Language/Annotated/Brosam
Brosam, masculine, Brosame, feminine, ‘crumb’; connected instinctively by Germans with Brot and Samen; compare, however, Middle High German brôsem, brôsme, Old High German brôsma, Old Low German brôsmo, ‘crumb, fragment’ (Gothic *brausma, ‘crumb,’ is not recorded). It is related either to the Teutonic root brut, which appears in Anglo-Saxon breótan, ‘to break,’ or to Anglo-Saxon brysan, Old French bruiser (English to bruise), from a Keltic-Teutonic root brū̆s, which the Upper German dialects preserve in brösolen; ‘to crumble’ (whence, too, Old Slovenian brŭselŭ, ‘sherd,’ brŭsnąti, ‘to wipe off, rub off’).