An Etymological Dictionary of the German Language/Annotated/Fladen

Fladen, masculine, ‘flat cake, cow dung,’ from Middle High German vlade, masculine, ‘broad, thin cake,’ Old High German flado, ‘offering-cake’; corresponds to Dutch vlade vla, feminine, ‘pancake,’ Middle English flaþe (Gothic *flaþa). Pre-Teutonic platan- or plathan- would have to be assumed, perhaps with the primitively sense, ‘surface, flat thing’; compare Greek πλατύς, ‘broad’; Greek πλάθανον (θ for Aryan th), ‘cake-mould’; Sanscrit pṛthús, ‘broad’ (akin to Sanscrit pṛthivî, ‘earth,’ under Feld), práthas, neuter, ‘breadth,’ Lithuanian platùs, ‘broad.’ Allied to the graded forms plôth, Latin Plôtus, Plautus, literally ‘flatfooted,’ semiplôtia, ‘slipper,’ Middle High German vluoder, ‘flounder,’ literally ‘flat fish.’ Remoter cognates of the whole class are Old Icelandic flatr, Old High German flaȥ, ‘level, flat.’ From Fladen, which is probably West Teutonic only, arc derived the early Middle Latin flado, Italian fiadone, ‘honeycomb,’ French flan, ‘flat cake, custard’ (whence English flawn, ‘a kind of custard’). Compare for its meaning Middle High German breitinc, masculine, ‘a sort of biscuit,’ akin to breit.