Where does “tesen” come from?

tesen (Middle English) comes from Old English tǣsan, from Proto-West Germanic taisijan — to separate; to tug, to pluck; to shred.

Ancestry of “tesen”, step by step

Step	Language	Word	Meaning
1	Old English	tǣsan	to tease
2	Proto-West Germanic	taisijan	to separate; to tug, to pluck; to shred

tesen — Etymology, Origin & Word History | Etymology Explorer