Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Proto-Celtic *kakkā

→ Breton cac'h (mention)
→ Welsh cachu (inherited)
→ Welsh cach (mention)
→ Galician caca (derived)
→ Manx keck (inherited)
→ Cornish caugh (mention)