Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh -ar
Proto-Brythonic *-ar (inherited)
Proto-Celtic *-aros (inherited)
Welsh byddar (mention)
Proto-Indo-European *-Hrós (inherited)

Welsh cynnar (suffix)
Welsh -gar (compound)
Welsh diweddar (suffix)