Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Cornish Iwerdhon
Breton Iwerzhon (cognate)
Proto-Celtic *Φīweryū (inherited)
Irish Éire (cognate)
Proto-Indo-European *piHweryon- (inherited)
Proto-Indo-European *piHwer- (mention)
Old Irish Ériu (cognate)

Welsh Iwerddon (cognate)
Cornish iwerdhonek (suffix)
Cornish Iwerdhonek (suffix)