Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh bych
Proto-Brythonic *bɨx (inherited)
Proto-Celtic *bikkos (inherited)
Welsh bach (doublet)
Welsh bychan (link)
Welsh Dinbych (link)
Welsh byddech (link)
Welsh byddych (link)

English Denbigh (compound)
Welsh bychod (suffix)