Where does “erball” come from?

erball (Old Irish) comes from Proto-Celtic ballos, from Proto-Indo-European bʰel-, from Proto-Indo-European bʰōl-.

Ancestry of “erball”, step by step

Step	Language	Word	Meaning
1	Proto-Celtic	ballos	member, penis
2	Proto-Indo-European	bʰel-	to sound; to speak, roar, bark; shiny, white; to...
3	Proto-Indo-European	bʰōl-	—

erball — Etymology, Origin & Word History | Etymology Explorer