Where does “Ῑ̓́λῐον” come from?

Ῑ̓́λῐον (Ancient Greek) comes from Hittite ??? — Wilusa; {{w|Wilusa}}.

Ancestry of “Ῑ̓́λῐον”, step by step

Step	Language	Word	Meaning
1	Hittite	???	Wilusa; {{w\|Wilusa}}

Ῑ̓́λῐον — Etymology, Origin & Word History | Etymology Explorer