"to be weighed down or oppresssed by cares or worries, be concerned about" (archaic), early 12c., a figurative use, via Anglo-French from Old North French carkier "to load, burden," from Late Latin carcare "to load a wagon or cart," from Latin carrus "wagon" (see car). Compare Old North French carguer "charger," corresponding to Old French chargier. The literal sense in English, "to load, put a burden on," is from c. 1300. Related: Carked; carking.
Also as a noun in Middle English and after, "charge, responsibility; anxiety, worry; burden on the mind or spirit," (c. 1300), from Anglo-French karke, from Old North French form of Old French carche, variant of charge "load, burden, imposition" (source of charge (n.)).