Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Manx doon
Proto-Celtic *dūnom (inherited)
Manx dooin (link)
Old Irish dúnaid (inherited)
Old Irish dúinid (mention)
Old Irish dún (inherited)

Manx dooin (link)
Manx dooney (suffix)