Where does “Hiberno American” come from?

Hiberno American (English) comes from English Hiberno-, from Latin Hibernia, from Latin Ivernia, from Ancient Greek Ἰ̄ουερνία, from Primitive Irish *Īweriū, from Proto-Celtic Φīweryū, from Proto-Indo-European piHweryon-, from Proto-Indo-European peyH- — fat, milk.

Ancestry of “Hiberno American”, step by step

StepLanguageWordMeaning
1EnglishHiberno-Relating to Ireland and/or Irish culture
2LatinHiberniaIreland
3LatinIvernia—
4Ancient GreekἸ̄ουερνίαIreland
5Primitive Irish*Īweriū—
6Proto-CelticΦīweryū—
7Proto-Indo-EuropeanpiHweryon-—
8Proto-Indo-EuropeanpeyH-fat, milk
Every word from Proto-Indo-European peyH- →Every word from Proto-Indo-European piHweryon- →Every word from Proto-Celtic Φīweryū →