Where does “ستین سنه” come from?

ستین سنه (Ottoman Turkish) comes from Arabic سَنَة, from Proto-Semitic šanat- — year.

Ancestry of “ستین سنه”, step by step

ستین سنه traces back through two separate lines of ancestry.

via Arabic سَنَة

Step	Language	Word	Meaning
1	Arabic	سَنَة	year
2	Proto-Semitic	šanat-	year

via Arabic ستون

Step	Language	Word	Meaning
1	Arabic	ستون	sixty; sixtieth
2	Arabic	سِتّ	six

Every word from Proto-Semitic šanat- →Every word from Arabic سَنَة →