Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh dadl
Proto-Brythonic *dadl (inherited)
Proto-Celtic *datlā (inherited)
Irish dáil (cognate)
Proto-Indo-European *dʰeh₁- (root)

Welsh dadlau (mention)
Welsh cynhadledd (affix)