Where does “Ionius” come from?

Ionius (Latin) comes from Latin Iōnia, from Ancient Greek Ἰωνία, from Ancient Greek -ῐ́ᾱ, from Proto-Indo-European -íh₂, from Proto-Indo-European -h₂ — Creates collective nouns, which refer to groups...

Ionius (Latin): of or belonging to Ionia, Ionian

Definitions

of or belonging to Ionia, Ionian

Ancestry of “Ionius”, step by step

Step	Language	Word	Meaning
1	Latin	Iōnia	—
2	Ancient Greek	Ἰωνία	Ionia
3	Ancient Greek	-ῐ́ᾱ	{{l\|en\|-ia}}; "suffix forming abstract feminine...
4	Proto-Indo-European	-íh₂	—
5	Proto-Indo-European	-h₂	Creates collective nouns, which refer to groups...

Every word from Proto-Indo-European -h₂ →Every word from Ancient Greek -ῐ́ᾱ →Every word from Ancient Greek Ἰωνία →