Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh llydan
Proto-Brythonic *llɨdan (inherited)
Proto-Celtic *ɸlitanos (inherited)

Welsh band llydan (affix)
Welsh Llydaw (mention)
Irish leathan (cognate)
Manx lhean (cognate)
Old Irish lethan (cognate)