Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Estonian kaksik
Estonian kaks (affix)
Estonian -ik (affix)
Finnish kaksikko (cognate)
Proto-Finnic *kakcikko (inherited)

Estonian -ik (link)
Finnish kaksikko (cognate)
Finnish kaksonen (cognate)