Where does “Pannonia” come from?

Pannonia derives from Latin Pannonia, ultimately from Proto-Indo-European pen-, though the exact semantic connection remains unclear.

Ancestry of “Pannonia”, step by step

Step	Language	Word	Meaning
1	Latin	Pannonia	—
2	Proto-Indo-European	pen-	bog, mire; moist; wet; mud; swamp; water; mire,...

Pannonia — Etymology, Origin & Word History | Etymology Explorer