Where does “-ῐ́λος” come from?

-ῐ́λος (Ancient Greek) comes from Proto-Hellenic *-illos, from Proto-Indo-European *-illos.

Ancestry of “-ῐ́λος”, step by step

Step	Language	Word	Meaning
1	Proto-Hellenic	*-illos	—
2	Proto-Indo-European	*-illos	—