Where does “Gregorio” come from?

Gregorio comes from Italian Gregorio, from Latin Gregorius, from Ancient Greek Γρηγόριος, formed with the Ancient Greek suffix -ιος from Proto-Indo-European -yós.

Ancestry of “Gregorio”, step by step

Step	Language	Word	Meaning
1	Italian	Gregorio	Gregory
2	Latin	Grēgorius	—
3	Ancient Greek	Γρηγόριος	watchful, vigilant
4	Ancient Greek	-ῐος	belonging to; of”, “belonging to”, “pertaining to
5	Proto-Indo-European	-yós	Creates adjectives from noun or verb stems

Every word from Proto-Indo-European -yós →Every word from Ancient Greek -ῐος →Every word from Ancient Greek Γρηγόριος →