An Etymological Dictionary of the German Language/Schmuck
Schmuck, m., ‘adornment, finery,’ ModHG. only, in MidHG. gesmuc, ‘adornment, embellishment,’ allied to schmücken, MidHG. smücken, ‘to wind, press close, dress, adorn.’ The Teut. root smug (pre-Teut. smuk) in schmiegen, of which schmücken is an intensive form, was frequently used orig. to form words signifying ‘to dress,’ and is also found in the name of a sort of under-garment or shirt, OHG. smoccho, AS. smocc (comp. E. smock). The adj. schmuck, ‘tidy, smart,’ ModHG. only, is derived from LG. (comp. North Fris. smok), whence also E. smug (or from Dan. smuk).