Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh sych
Proto-Brythonic *sɨx (inherited)
Latin siccus (derived)
Old Welsh sich (inherited)
Middle Welsh sych (inherited)

Welsh sychu (suffix)
Welsh sychin (compound)
Welsh sychnant (compound)
Esperanto seka (mention)