An Etymological Dictionary of the German Language/Annotated/Schalk
Schalk, masculine, ‘rogue, knave,’ from Middle High German schalc, masculine, ‘servant, serf; person of servile character, especially cunning person,’ Old High German scalch, masculine, ‘servant’; corresponding to Gothic skalks, Old Icelandic skálkr, Anglo-Saxon sčealc, masculine, ‘retainer, man’ (so too the corresponding feminine sčylčen, ‘‘maid-servant’). The evolution in meaning is similar to that of Anglo-Saxon čyfes and wealh; see Kebse and welsch. Schalk passed at an early period into Italian, in which scalco signifies ‘head-cook.’ It is worthy of note that the meaning of the word is lifted into a higher plane in its transition from Middle High German to Modern High German; it is thus defined by Goethe, ‘one who plays a good-humoured practical joke.’