Breton Iwerzhon

← Proto-Celtic *Φīweryū (inherited)

← Welsh Iwerddon (cognate)

← Irish Éire (cognate)

← Proto-Indo-European *piHweryon- (inherited)

← Proto-Indo-European *piHwer- (mention)

← Old Irish Ériu (cognate)

→ Breton iwerzhoneg (suffix)

→ Welsh Iwerddon (cognate)

→ Cornish Iwerdhon (cognate)