From Middle English werk, warch, from Old English wærc, wræc, from Proto-Germanic *warkiz ("pain"), from Proto-Indo-European *werǵ- ("to make, work, act"). Cognate with Swedish värk ("ache, pain"), Icelandic verkur ("pain"). Related to work.
From Middle English werken, warchen, from Old English wærcan ("to be in pain"). Cognate with Swedish värka ("to ache, pain"), Icelandic verkja ("to pain"). See above.