Where does “wístōr” come from?

wístōr (Proto-Hellenic) comes from Proto-Indo-European wéydtōr, from Indo-European *weyd-.

Ancestry of “wístōr”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	wéydtōr	one who has seen, one who knows
2	Indo-European	*weyd-	—

wístōr — Etymology, Origin & Word History | Etymology Explorer