Where does “ミラノ” come from?

ミラノ (Japanese) comes from Italian Milano, from Latin Mediolanum, from Gaulish lānom — plain, field.

Ancestry of “ミラノ”, step by step

Step	Language	Word	Meaning
1	Italian	Milano	Milan
2	Latin	Mediolanum	Milan
3	Gaulish	lānom	plain, field

ミラノ — Etymology, Origin & Word History | Etymology Explorer