Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh cy-
Welsh cyf- (mention)
Cornish ke- (cognate)
Cornish ky- (cognate)

Welsh cysyniad (affix)
Welsh cyngerdd (affix)
Welsh cysgod (prefix)
Welsh cytref (affix)
Welsh crybwyll (affix)
French cohue (cognate)