Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh cnau
Proto-Brythonic *know (inherited)
Proto-Celtic *knūs (inherited)
English nut (cognate)
Proto-Indo-European *knew- (inherited)
Latin nux (cognate)

Welsh cneuen (affix)
Welsh cnewyll (mention)
Welsh cneua (affix)
Irish cnó (cognate)
Scottish Gaelic cnò (cognate)
Manx cro (cognate)