←
Old English þearf (cognate)
←
Proto-Indo-European *terp- (root)
←
Icelandic þörf (cognate)
←
Norwegian Nynorsk tarv (doublet)
←
Old Norse þǫrf (inherited)
←
Old Norse torf (inherited)
→
Norwegian Nynorsk tarv (doublet)
→
Norwegian Nynorsk torvmyr (affix)