Where does “اوكش” come from?

اوكش (Old Anatolian Turkish) comes from Proto-Turkic *üküĺ, from Proto-Turkic *ük-.

Ancestry of “اوكش”, step by step

Step	Language	Word	Meaning
1	Proto-Turkic	*üküĺ	—
2	Proto-Turkic	*ük-	—