Where does “þarf” come from?

þarf (Proto-Germanic) comes from Proto-Germanic þurbaną, from Proto-Indo-European terp- — to satisfy.

Ancestry of “þarf”, step by step

Step	Language	Word	Meaning
1	Proto-Germanic	þurbaną	to need, to require; to have to
2	Proto-Indo-European	terp-	to satisfy

þarf — Etymology, Origin & Word History | Etymology Explorer