Where does “naszyć” come from?

naszyć (Polish) comes from Polish na-, from Old Polish na-, from Proto-Slavic na- — on.

Ancestry of “naszyć”, step by step

Step	Language	Word	Meaning
1	Polish	na-	—
2	Old Polish	na-	—
3	Proto-Slavic	na-	on

naszyć — Etymology, Origin & Word History | Etymology Explorer