Where does “þreten” come from?

þreten (Middle English) comes from Old English þrēatian, from Proto-Indo-European trewd- — to push, to thrust.

Ancestry of “þreten”, step by step

Step	Language	Word	Meaning
1	Old English	þrēatian	to threaten, to push; to press, oppress, repress,...
2	Proto-Indo-European	trewd-	to push, to thrust

þreten — Etymology, Origin & Word History | Etymology Explorer