pilliwinks

From Middle English pirewinkes (“instrument of torture for squeezing the thumbs, thumbscrew”) [and other forms]; further origin unknown. It has been suggested that the word is a variant of Middle English pervink, pervinke (“periwinkle (plant; Vinca minor or Vinca major); (figuratively) evil man”), but the Oxford English Dictionary doubts this due to the difference in meaning. Compare Swedish pille-, related to pilla (“fiddle with the fingers”).

来源：wiktionary