Where does “ⲇⲓⲟⲥ” come from?

ⲇⲓⲟⲥ (Coptic) comes from Ancient Greek δῖος, from Proto-Hellenic diyyos, from Proto-Indo-European diwyós, from Proto-Indo-European dyew- — to be bright; sky, heaven.

Ancestry of “ⲇⲓⲟⲥ”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	δῖος	heavenly, divine, noble
2	Proto-Hellenic	diyyos	divine, noble
3	Proto-Indo-European	diwyós	heavenly
4	Proto-Indo-European	dyew-	to be bright; sky, heaven

Every word from Proto-Indo-European dyew- →Every word from Proto-Indo-European diwyós →Every word from Proto-Hellenic diyyos →