Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Irish geir
Proto-Celtic *gʷeress (inherited)
Welsh gwêr (cognate)
Proto-Indo-European *gʷʰer- (derived)
Proto-Indo-European *ǵʰwer- (mention)
Middle Irish geir (inherited)

Irish geireach (suffix)