Where does “flintaz” come from?

flintaz (Proto-Germanic) comes from Proto-Indo-European splind-, from Proto-Indo-European (s)plei- — to split, splice; to divide, split, splice.

Ancestry of “flintaz”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	splind-	to split, cleave; split
2	Proto-Indo-European	(s)plei-	to split, splice; to divide, split, splice

flintaz — Etymology, Origin & Word History | Etymology Explorer