Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Irish rún
Proto-Celtic *rūnā (inherited)
Welsh rhin (cognate)
Scottish Gaelic rùn (cognate)
Manx roon (cognate)
Old Irish rún (inherited)

Irish rúnaí (suffix)
Irish rúnda (affix)