Where does “Éfeso” come from?

Éfeso (Spanish) comes from Ancient Greek Ἔφεσος, from Luwian Apa-ša.

Ancestry of “Éfeso”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	Ἔφεσος	Ephesus
2	Luwian	Apa-ša	—

Éfeso — Etymology, Origin & Word History | Etymology Explorer